host_thread.py

# -*- coding: utf-8 -*-

##
# Copyright 2015 Telefónica Investigación y Desarrollo, S.A.U.
# This file is part of openvim
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
#
# For those usages not covered by the Apache License, Version 2.0 please
# contact with: nfvlabs@tid.es
##

'''
This is thread that interact with the host and the libvirt to manage VM
One thread will be launched per host 
'''
__author__="Pablo Montes, Alfonso Tierno"
__date__ ="$10-jul-2014 12:07:15$"


import json
import yaml
import threading
import time
import Queue
import paramiko
from jsonschema import validate as js_v, exceptions as js_e
import libvirt
from vim_schema import localinfo_schema, hostinfo_schema
import random
#from logging import Logger
#import auxiliary_functions as af

#TODO: insert a logging system

class host_thread(threading.Thread):
    def __init__(self, name, host, user, db, db_lock, test, image_path, host_id, version, develop_mode, develop_bridge_iface):
        '''Init a thread.
        Arguments: 
            'id' number of thead
            'name' name of thread
            'host','user':  host ip or name to manage and user
            'db', 'db_lock': database class and lock to use it in exclusion
        '''
        threading.Thread.__init__(self)
        self.name = name
        self.host = host
        self.user = user
        self.db = db
        self.db_lock = db_lock
        self.test = test
        self.develop_mode = develop_mode
        self.develop_bridge_iface = develop_bridge_iface
        self.image_path = image_path
        self.host_id = host_id
        self.version = version
        
        self.xml_level = 0
        #self.pending ={}
        
        self.server_status = {} #dictionary with pairs server_uuid:server_status 
        self.pending_terminate_server =[] #list  with pairs (time,server_uuid) time to send a terminate for a server being destroyed
        self.next_update_server_status = 0 #time when must be check servers status
        
        self.hostinfo = None 
        
        self.queueLock = threading.Lock()
        self.taskQueue = Queue.Queue(2000)
        
    def ssh_connect(self):
        try:
            #Connect SSH
            self.ssh_conn = paramiko.SSHClient()
            self.ssh_conn.set_missing_host_key_policy(paramiko.AutoAddPolicy())
            self.ssh_conn.load_system_host_keys()
            self.ssh_conn.connect(self.host, username=self.user, timeout=10) #, None)
        except paramiko.ssh_exception.SSHException as e:
            text = e.args[0]
            print self.name, ": ssh_connect ssh Exception:", text
        
    def load_localinfo(self):
        if not self.test:
            try:
                #Connect SSH
                self.ssh_connect()
    
                command = 'mkdir -p ' +  self.image_path
                #print self.name, ': command:', command
                (_, stdout, stderr) = self.ssh_conn.exec_command(command)
                content = stderr.read()
                if len(content) > 0:
                    print self.name, ': command:', command, "stderr:", content

                command = 'cat ' +  self.image_path + '/.openvim.yaml'
                #print self.name, ': command:', command
                (_, stdout, stderr) = self.ssh_conn.exec_command(command)
                content = stdout.read()
                if len(content) == 0:
                    print self.name, ': command:', command, "stderr:", stderr.read()
                    raise paramiko.ssh_exception.SSHException("Error empty file ")
                self.localinfo = yaml.load(content)
                js_v(self.localinfo, localinfo_schema)
                self.localinfo_dirty=False
                if 'server_files' not in self.localinfo:
                    self.localinfo['server_files'] = {}
                print self.name, ': localinfo load from host'
                return
    
            except paramiko.ssh_exception.SSHException as e:
                text = e.args[0]
                print self.name, ": load_localinfo ssh Exception:", text
            except libvirt.libvirtError as e:
                text = e.get_error_message()
                print self.name, ": load_localinfo libvirt Exception:", text
            except yaml.YAMLError as exc:
                text = ""
                if hasattr(exc, 'problem_mark'):
                    mark = exc.problem_mark
                    text = " at position: (%s:%s)" % (mark.line+1, mark.column+1)
                print self.name, ": load_localinfo yaml format Exception", text
            except js_e.ValidationError as e:
                text = ""
                if len(e.path)>0: text=" at '" + ":".join(map(str, e.path))+"'"
                print self.name, ": load_localinfo format Exception:", text, e.message 
            except Exception as e:
                text = str(e)
                print self.name, ": load_localinfo Exception:", text
        
        #not loaded, insert a default data and force saving by activating dirty flag
        self.localinfo = {'files':{}, 'server_files':{} } 
        #self.localinfo_dirty=True
        self.localinfo_dirty=False

    def load_hostinfo(self):
        if self.test:
            return;
        try:
            #Connect SSH
            self.ssh_connect()


            command = 'cat ' +  self.image_path + '/hostinfo.yaml'
            #print self.name, ': command:', command
            (_, stdout, stderr) = self.ssh_conn.exec_command(command)
            content = stdout.read()
            if len(content) == 0:
                print self.name, ': command:', command, "stderr:", stderr.read()
                raise paramiko.ssh_exception.SSHException("Error empty file ")
            self.hostinfo = yaml.load(content)
            js_v(self.hostinfo, hostinfo_schema)
            print self.name, ': hostlinfo load from host', self.hostinfo
            return

        except paramiko.ssh_exception.SSHException as e:
            text = e.args[0]
            print self.name, ": load_hostinfo ssh Exception:", text
        except libvirt.libvirtError as e:
            text = e.get_error_message()
            print self.name, ": load_hostinfo libvirt Exception:", text
        except yaml.YAMLError as exc:
            text = ""
            if hasattr(exc, 'problem_mark'):
                mark = exc.problem_mark
                text = " at position: (%s:%s)" % (mark.line+1, mark.column+1)
            print self.name, ": load_hostinfo yaml format Exception", text
        except js_e.ValidationError as e:
            text = ""
            if len(e.path)>0: text=" at '" + ":".join(map(str, e.path))+"'"
            print self.name, ": load_hostinfo format Exception:", text, e.message 
        except Exception as e:
            text = str(e)
            print self.name, ": load_hostinfo Exception:", text
        
        #not loaded, insert a default data 
        self.hostinfo = None 
        
    def save_localinfo(self, tries=3):
        if self.test:
            self.localinfo_dirty = False
            return
        
        while tries>=0:
            tries-=1
            
            try:
                command = 'cat > ' +  self.image_path + '/.openvim.yaml'
                print self.name, ': command:', command
                (stdin, _, _) = self.ssh_conn.exec_command(command)
                yaml.safe_dump(self.localinfo, stdin, explicit_start=True, indent=4, default_flow_style=False, tags=False, encoding='utf-8', allow_unicode=True)
                self.localinfo_dirty = False
                break #while tries
    
            except paramiko.ssh_exception.SSHException as e:
                text = e.args[0]
                print self.name, ": save_localinfo ssh Exception:", text
                if "SSH session not active" in text:
                    self.ssh_connect()
            except libvirt.libvirtError as e:
                text = e.get_error_message()
                print self.name, ": save_localinfo libvirt Exception:", text
            except yaml.YAMLError as exc:
                text = ""
                if hasattr(exc, 'problem_mark'):
                    mark = exc.problem_mark
                    text = " at position: (%s:%s)" % (mark.line+1, mark.column+1)
                print self.name, ": save_localinfo yaml format Exception", text
            except Exception as e:
                text = str(e)
                print self.name, ": save_localinfo Exception:", text

    def load_servers_from_db(self):
        self.db_lock.acquire()
        r,c = self.db.get_table(SELECT=('uuid','status', 'image_id'), FROM='instances', WHERE={'host_id': self.host_id})
        self.db_lock.release()

        self.server_status = {}
        if r<0:
            print self.name, ": Error getting data from database:", c
            return
        for server in c:
            self.server_status[ server['uuid'] ] = server['status']
            
            #convert from old version to new one
            if 'inc_files' in self.localinfo and server['uuid'] in self.localinfo['inc_files']:
                server_files_dict = {'source file': self.localinfo['inc_files'][ server['uuid'] ] [0],  'file format':'raw' }
                if server_files_dict['source file'][-5:] == 'qcow2':
                    server_files_dict['file format'] = 'qcow2'
                    
                self.localinfo['server_files'][ server['uuid'] ] = { server['image_id'] : server_files_dict }
        if 'inc_files' in self.localinfo:
            del self.localinfo['inc_files']
            self.localinfo_dirty = True
    
    def delete_unused_files(self):
        '''Compares self.localinfo['server_files'] content with real servers running self.server_status obtained from database
        Deletes unused entries at self.loacalinfo and the corresponding local files.
        The only reason for this mismatch is the manual deletion of instances (VM) at database
        ''' 
        if self.test:
            return
        for uuid,images in self.localinfo['server_files'].items():
            if uuid not in self.server_status:
                for localfile in images.values():
                    try:
                        print self.name, ": deleting file '%s' of unused server '%s'" %(localfile['source file'], uuid)
                        self.delete_file(localfile['source file'])
                    except paramiko.ssh_exception.SSHException as e:
                        print self.name, ": Exception deleting file '%s': %s" %(localfile['source file'], str(e))
                del self.localinfo['server_files'][uuid]
                self.localinfo_dirty = True
   
    def insert_task(self, task, *aditional):
        try:
            self.queueLock.acquire()
            task = self.taskQueue.put( (task,) + aditional, timeout=5) 
            self.queueLock.release()
            return 1, None
        except Queue.Full:
            return -1, "timeout inserting a task over host " + self.name

    def run(self):
        while True:
            self.load_localinfo()
            self.load_hostinfo()
            self.load_servers_from_db()
            self.delete_unused_files()
            while True:
                self.queueLock.acquire()
                if not self.taskQueue.empty():
                    task = self.taskQueue.get()
                else:
                    task = None
                self.queueLock.release()
    
                if task is None:
                    now=time.time()
                    if self.localinfo_dirty:
                        self.save_localinfo()
                    elif self.next_update_server_status < now:
                        self.update_servers_status()
                        self.next_update_server_status = now + 5
                    elif len(self.pending_terminate_server)>0 and self.pending_terminate_server[0][0]<now:
                        self.server_forceoff()
                    else:
                        time.sleep(1)
                    continue        
    
                if task[0] == 'instance':
                    print self.name, ": processing task instance", task[1]['action']
                    retry=0
                    while retry <2:
                        retry += 1
                        r=self.action_on_server(task[1], retry==2)
                        if r>=0: 
                            break
                elif task[0] == 'image':
                    pass
                elif task[0] == 'exit':
                    print self.name, ": processing task exit"
                    self.terminate()
                    return 0
                elif task[0] == 'reload':
                    print self.name, ": processing task reload terminating and relaunching"
                    self.terminate()
                    break
                elif task[0] == 'edit-iface':
                    print self.name, ": processing task edit-iface port=%s, old_net=%s, new_net=%s" % (task[1], task[2], task[3])
                    self.edit_iface(task[1], task[2], task[3])
                elif task[0] == 'restore-iface':
                    print self.name, ": processing task restore-iface %s mac=%s" % (task[1], task[2])
                    self.restore_iface(task[1], task[2])
                else:
                    print self.name, ": unknown task", task
                
    def server_forceoff(self, wait_until_finished=False):
        while len(self.pending_terminate_server)>0:
            now = time.time()
            if self.pending_terminate_server[0][0]>now:
                if wait_until_finished:
                    time.sleep(1)
                    continue
                else:
                    return
            req={'uuid':self.pending_terminate_server[0][1],
                'action':{'terminate':'force'},
                'status': None
            }
            self.action_on_server(req)
            self.pending_terminate_server.pop(0)
    
    def terminate(self):
        try:
            self.server_forceoff(True)
            if self.localinfo_dirty:
                self.save_localinfo()
            if not self.test:
                self.ssh_conn.close()
        except Exception as e:
            text = str(e)
            print self.name, ": terminate Exception:", text
        print self.name, ": exit from host_thread" 

    def get_local_iface_name(self, generic_name):
        if self.hostinfo != None and "iface_names" in self.hostinfo and generic_name in self.hostinfo["iface_names"]:
            return self.hostinfo["iface_names"][generic_name]
        return generic_name
        
    def create_xml_server(self, server, dev_list, server_metadata={}):
        """Function that implements the generation of the VM XML definition.
        Additional devices are in dev_list list
        The main disk is upon dev_list[0]"""
        
    #get if operating system is Windows        
        windows_os = False
        os_type = server_metadata.get('os_type', None)
        if os_type == None and 'metadata' in dev_list[0]:
            os_type = dev_list[0]['metadata'].get('os_type', None)
        if os_type != None and os_type.lower() == "windows":
            windows_os = True
    #get type of hard disk bus  
        bus_ide = True if windows_os else False   
        bus = server_metadata.get('bus', None)
        if bus == None and 'metadata' in dev_list[0]:
            bus = dev_list[0]['metadata'].get('bus', None)
        if bus != None:
            bus_ide = True if bus=='ide' else False
            
        self.xml_level = 0

        text = "<domain type='kvm'>"
    #get topology
        topo = server_metadata.get('topology', None)
        if topo == None and 'metadata' in dev_list[0]:
            topo = dev_list[0]['metadata'].get('topology', None)
    #name
        name = server.get('name','') + "_" + server['uuid']
        name = name[:58]  #qemu impose a length  limit of 59 chars or not start. Using 58
        text += self.inc_tab() + "<name>" + name+ "</name>"
    #uuid
        text += self.tab() + "<uuid>" + server['uuid'] + "</uuid>" 
        
        numa={}
        if 'extended' in server and server['extended']!=None and 'numas' in server['extended']:
            numa = server['extended']['numas'][0]
    #memory
        use_huge = False
        memory = int(numa.get('memory',0))*1024*1024 #in KiB
        if memory==0:
            memory = int(server['ram'])*1024;
        else:
            if not self.develop_mode:
                use_huge = True
        if memory==0:
            return -1, 'No memory assigned to instance'
        memory = str(memory)
        text += self.tab() + "<memory unit='KiB'>" +memory+"</memory>" 
        text += self.tab() + "<currentMemory unit='KiB'>" +memory+ "</currentMemory>"
        if use_huge:
            text += self.tab()+'<memoryBacking>'+ \
                self.inc_tab() + '<hugepages/>'+ \
                self.dec_tab()+ '</memoryBacking>'

    #cpu
        use_cpu_pinning=False
        vcpus = int(server.get("vcpus",0))
        cpu_pinning = []
        if 'cores-source' in numa:
            use_cpu_pinning=True
            for index in range(0, len(numa['cores-source'])):
                cpu_pinning.append( [ numa['cores-id'][index], numa['cores-source'][index] ] )
                vcpus += 1
        if 'threads-source' in numa:
            use_cpu_pinning=True
            for index in range(0, len(numa['threads-source'])):
                cpu_pinning.append( [ numa['threads-id'][index], numa['threads-source'][index] ] )
                vcpus += 1
        if 'paired-threads-source' in numa:
            use_cpu_pinning=True
            for index in range(0, len(numa['paired-threads-source'])):
                cpu_pinning.append( [numa['paired-threads-id'][index][0], numa['paired-threads-source'][index][0] ] )
                cpu_pinning.append( [numa['paired-threads-id'][index][1], numa['paired-threads-source'][index][1] ] )
                vcpus += 2
        
        if use_cpu_pinning and not self.develop_mode:
            text += self.tab()+"<vcpu placement='static'>" +str(len(cpu_pinning)) +"</vcpu>" + \
                self.tab()+'<cputune>'
            self.xml_level += 1
            for i in range(0, len(cpu_pinning)):
                text += self.tab() + "<vcpupin vcpu='" +str(cpu_pinning[i][0])+ "' cpuset='" +str(cpu_pinning[i][1]) +"'/>"
            text += self.dec_tab()+'</cputune>'+ \
                self.tab() + '<numatune>' +\
                self.inc_tab() + "<memory mode='strict' nodeset='" +str(numa['source'])+ "'/>" +\
                self.dec_tab() + '</numatune>'
        else:
            if vcpus==0:
                return -1, "Instance without number of cpus"
            text += self.tab()+"<vcpu>" + str(vcpus)  + "</vcpu>"

    #boot
        boot_cdrom = False
        for dev in dev_list:
            if dev['type']=='cdrom' :
                boot_cdrom = True
                break
        text += self.tab()+ '<os>' + \
            self.inc_tab() + "<type arch='x86_64' machine='pc'>hvm</type>"
        if boot_cdrom:
            text +=  self.tab() + "<boot dev='cdrom'/>" 
        text +=  self.tab() + "<boot dev='hd'/>" + \
            self.dec_tab()+'</os>'
    #features
        text += self.tab()+'<features>'+\
            self.inc_tab()+'<acpi/>' +\
            self.tab()+'<apic/>' +\
            self.tab()+'<pae/>'+ \
            self.dec_tab() +'</features>'
        if windows_os or topo=="oneSocket":
            text += self.tab() + "<cpu mode='host-model'> <topology sockets='1' cores='%d' threads='1' /> </cpu>"% vcpus
        else:
            text += self.tab() + "<cpu mode='host-model'></cpu>"
        text += self.tab() + "<clock offset='utc'/>" +\
            self.tab() + "<on_poweroff>preserve</on_poweroff>" + \
            self.tab() + "<on_reboot>restart</on_reboot>" + \
            self.tab() + "<on_crash>restart</on_crash>"
        text += self.tab() + "<devices>" + \
            self.inc_tab() + "<emulator>/usr/libexec/qemu-kvm</emulator>" + \
            self.tab() + "<serial type='pty'>" +\
            self.inc_tab() + "<target port='0'/>" + \
            self.dec_tab() + "</serial>" +\
            self.tab() + "<console type='pty'>" + \
            self.inc_tab()+ "<target type='serial' port='0'/>" + \
            self.dec_tab()+'</console>'
        if windows_os:
            text += self.tab() + "<controller type='usb' index='0'/>" + \
                self.tab() + "<controller type='ide' index='0'/>" + \
                self.tab() + "<input type='mouse' bus='ps2'/>" + \
                self.tab() + "<sound model='ich6'/>" + \
                self.tab() + "<video>" + \
                self.inc_tab() + "<model type='cirrus' vram='9216' heads='1'/>" + \
                self.dec_tab() + "</video>" + \
                self.tab() + "<memballoon model='virtio'/>" + \
                self.tab() + "<input type='tablet' bus='usb'/>" #TODO revisar

#>             self.tab()+'<alias name=\'hostdev0\'/>\n' +\
#>             self.dec_tab()+'</hostdev>\n' +\
#>             self.tab()+'<input type=\'tablet\' bus=\'usb\'/>\n'
        if windows_os:
            text += self.tab() + "<graphics type='vnc' port='-1' autoport='yes'/>"
        else:
            #If image contains 'GRAPH' include graphics
            #if 'GRAPH' in image:
            text += self.tab() + "<graphics type='vnc' port='-1' autoport='yes' listen='0.0.0.0'>" +\
                self.inc_tab() + "<listen type='address' address='0.0.0.0'/>" +\
                self.dec_tab() + "</graphics>"

        vd_index = 'a'
        for dev in dev_list:
            bus_ide_dev = bus_ide
            if dev['type']=='cdrom' or dev['type']=='disk':
                if dev['type']=='cdrom':
                    bus_ide_dev = True
                text += self.tab() + "<disk type='file' device='"+dev['type']+"'>"
                if 'file format' in dev:
                    text += self.inc_tab() + "<driver name='qemu' type='"  +dev['file format']+ "' cache='writethrough'/>"
                if 'source file' in dev:
                    text += self.tab() + "<source file='" +dev['source file']+ "'/>"
                #elif v['type'] == 'block':
                #    text += self.tab() + "<source dev='" + v['source'] + "'/>"
                #else:
                #    return -1, 'Unknown disk type ' + v['type']
                vpci = dev.get('vpci',None)
                if vpci == None:
                    vpci = dev['metadata'].get('vpci',None)
                text += self.pci2xml(vpci)
               
                if bus_ide_dev:
                    text += self.tab() + "<target dev='hd" +vd_index+ "' bus='ide'/>"   #TODO allows several type of disks
                else:
                    text += self.tab() + "<target dev='vd" +vd_index+ "' bus='virtio'/>" 
                text += self.dec_tab() + '</disk>'
                vd_index = chr(ord(vd_index)+1)
            elif dev['type']=='xml':
                dev_text = dev['xml']
                if 'vpci' in dev:
                    dev_text = dev_text.replace('__vpci__', dev['vpci'])
                if 'source file' in dev:
                    dev_text = dev_text.replace('__file__', dev['source file'])
                if 'file format' in dev:
                    dev_text = dev_text.replace('__format__', dev['source file'])
                if '__dev__' in dev_text:
                    dev_text = dev_text.replace('__dev__', vd_index)
                    vd_index = chr(ord(vd_index)+1)
                text += dev_text
            else:
                return -1, 'Unknown device type ' + dev['type']

        net_nb=0
        bridge_interfaces = server.get('networks', [])
        for v in bridge_interfaces:
            #Get the brifge name
            self.db_lock.acquire()
            result, content = self.db.get_table(FROM='nets', SELECT=('provider',),WHERE={'uuid':v['net_id']} )
            self.db_lock.release()
            if result <= 0:
                print "create_xml_server ERROR getting nets",result, content
                return -1, content
            #ALF: Allow by the moment the 'default' bridge net because is confortable for provide internet to VM
            #I know it is not secure    
            #for v in sorted(desc['network interfaces'].itervalues()):
            model = v.get("model", None)
            if content[0]['provider']=='default':
                text += self.tab() + "<interface type='network'>" + \
                    self.inc_tab() + "<source network='" +content[0]['provider']+ "'/>"
            elif content[0]['provider'][0:7]=='macvtap':
                text += self.tab()+"<interface type='direct'>" + \
                    self.inc_tab() + "<source dev='" + self.get_local_iface_name(content[0]['provider'][8:]) + "' mode='bridge'/>" + \
                    self.tab() + "<target dev='macvtap0'/>"
                if windows_os:
                    text += self.tab() + "<alias name='net" + str(net_nb) + "'/>"
                elif model==None:
                    model = "virtio"
            elif content[0]['provider'][0:6]=='bridge':
                text += self.tab() + "<interface type='bridge'>" +  \
                    self.inc_tab()+"<source bridge='" +self.get_local_iface_name(content[0]['provider'][7:])+ "'/>"
                if windows_os:
                    text += self.tab() + "<target dev='vnet" + str(net_nb)+ "'/>" +\
                        self.tab() + "<alias name='net" + str(net_nb)+ "'/>"
                elif model==None:
                    model = "virtio"
            else:
                return -1, 'Unknown Bridge net provider ' + content[0]['provider']
            if model!=None:
                text += self.tab() + "<model type='" +model+ "'/>"
            if v.get('mac_address', None) != None:
                text+= self.tab() +"<mac address='" +v['mac_address']+ "'/>"
            text += self.pci2xml(v.get('vpci',None))
            text += self.dec_tab()+'</interface>'
            
            net_nb += 1

        interfaces = numa.get('interfaces', [])

        net_nb=0
        for v in interfaces:
            if self.develop_mode: #map these interfaces to bridges
                text += self.tab() + "<interface type='bridge'>" +  \
                    self.inc_tab()+"<source bridge='" +self.develop_bridge_iface+ "'/>"
                if windows_os:
                    text += self.tab() + "<target dev='vnet" + str(net_nb)+ "'/>" +\
                        self.tab() + "<alias name='net" + str(net_nb)+ "'/>"
                else:
                    text += self.tab() + "<model type='e1000'/>" #e1000 is more probable to be supported than 'virtio'
                if v.get('mac_address', None) != None:
                    text+= self.tab() +"<mac address='" +v['mac_address']+ "'/>"
                text += self.pci2xml(v.get('vpci',None))
                text += self.dec_tab()+'</interface>'
                continue
                
            if v['dedicated'] == 'yes':  #passthrought
                text += self.tab() + "<hostdev mode='subsystem' type='pci' managed='yes'>" + \
                    self.inc_tab() + "<source>"
                self.inc_tab()
                text += self.pci2xml(v['source'])
                text += self.dec_tab()+'</source>'
                text += self.pci2xml(v.get('vpci',None))
                if windows_os:
                    text += self.tab() + "<alias name='hostdev" + str(net_nb) + "'/>"
                text += self.dec_tab()+'</hostdev>'
                net_nb += 1
            else:        #sriov_interfaces
                #skip not connected interfaces
                if v.get("net_id") == None:
                    continue
                text += self.tab() + "<interface type='hostdev' managed='yes'>"
                self.inc_tab()
                if v.get('mac_address', None) != None:
                    text+= self.tab() + "<mac address='" +v['mac_address']+ "'/>"
                text+= self.tab()+'<source>'
                self.inc_tab()
                text += self.pci2xml(v['source'])
                text += self.dec_tab()+'</source>'
                if v.get('vlan',None) != None:
                    text += self.tab() + "<vlan>   <tag id='" + str(v['vlan']) + "'/>   </vlan>"
                text += self.pci2xml(v.get('vpci',None))
                if windows_os:
                    text += self.tab() + "<alias name='hostdev" + str(net_nb) + "'/>"
                text += self.dec_tab()+'</interface>'

            
        text += self.dec_tab()+'</devices>'+\
        self.dec_tab()+'</domain>'
        return 0, text
    
    def pci2xml(self, pci):
        '''from a pci format text XXXX:XX:XX.X generates the xml content of <address>
        alows an empty pci text'''
        if pci is None:
            return ""
        first_part = pci.split(':')
        second_part = first_part[2].split('.')
        return self.tab() + "<address type='pci' domain='0x" + first_part[0] + \
                    "' bus='0x" + first_part[1] + "' slot='0x" + second_part[0] + \
                    "' function='0x" + second_part[1] + "'/>" 
    
    def tab(self):
        """Return indentation according to xml_level"""
        return "\n" + ('  '*self.xml_level)
    
    def inc_tab(self):
        """Increment and return indentation according to xml_level"""
        self.xml_level += 1
        return self.tab()
    
    def dec_tab(self):
        """Decrement and return indentation according to xml_level"""
        self.xml_level -= 1
        return self.tab()
    
    def get_file_info(self, path):
        command = 'ls -lL --time-style=+%Y-%m-%dT%H:%M:%S ' + path
        print self.name, ': command:', command
        (_, stdout, _) = self.ssh_conn.exec_command(command)
        content = stdout.read()
        if len(content) == 0:
            return None # file does not exist
        else:
            return content.split(" ") #(permission, 1, owner, group, size, date, file)

    def qemu_get_info(self, path):
        command = 'qemu-img info ' + path
        print self.name, ': command:', command
        (_, stdout, stderr) = self.ssh_conn.exec_command(command)
        content = stdout.read()
        if len(content) == 0:
            error = stderr.read()
            print self.name, ": get_qemu_info error ", error
            raise paramiko.ssh_exception.SSHException("Error getting qemu_info: " + error)
        else:
            try: 
                return yaml.load(content)
            except yaml.YAMLError as exc:
                text = ""
                if hasattr(exc, 'problem_mark'):
                    mark = exc.problem_mark
                    text = " at position: (%s:%s)" % (mark.line+1, mark.column+1)
                print self.name, ": get_qemu_info yaml format Exception", text
                raise paramiko.ssh_exception.SSHException("Error getting qemu_info yaml format" + text)

    def qemu_change_backing(self, inc_file, new_backing_file):
        command = 'qemu-img rebase -u -b ' + new_backing_file + ' ' + inc_file 
        print self.name, ': command:', command
        (_, _, stderr) = self.ssh_conn.exec_command(command)
        content = stderr.read()
        if len(content) == 0:
            return 0
        else:
            print self.name, ": qemu_change_backing error: ", content
            return -1
    
    def get_notused_filename(self, proposed_name, suffix=''):
        '''Look for a non existing file_name in the host
            proposed_name: proposed file name, includes path
            suffix: suffix to be added to the name, before the extention
        '''
        extension = proposed_name.rfind(".")
        slash = proposed_name.rfind("/")
        if extension < 0 or extension < slash: # no extension
            extension = len(proposed_name)
        target_name = proposed_name[:extension] + suffix + proposed_name[extension:]
        info = self.get_file_info(target_name)
        if info is None:
            return target_name
        
        index=0
        while info is not None:
            target_name = proposed_name[:extension] + suffix +  "-" + str(index) + proposed_name[extension:]
            index+=1
            info = self.get_file_info(target_name) 
        return target_name
    
    def get_notused_path(self, proposed_path, suffix=''):
        '''Look for a non existing path at database for images
            proposed_path: proposed file name, includes path
            suffix: suffix to be added to the name, before the extention
        '''
        extension = proposed_path.rfind(".")
        if extension < 0:
            extension = len(proposed_path)
        if suffix != None:
            target_path = proposed_path[:extension] + suffix + proposed_path[extension:]
        index=0
        while True:
            r,_=self.db.get_table(FROM="images",WHERE={"path":target_path})
            if r<=0:
                return target_path
            target_path = proposed_path[:extension] + suffix +  "-" + str(index) + proposed_path[extension:]
            index+=1

    
    def delete_file(self, file_name):
        command = 'rm -f '+file_name
        print self.name, ': command:', command
        (_, _, stderr) = self.ssh_conn.exec_command(command)
        error_msg = stderr.read()
        if len(error_msg) > 0:
            raise paramiko.ssh_exception.SSHException("Error deleting file: " + error_msg)

    def copy_file(self, source, destination, perserve_time=True):
        command = 'cp --no-preserve=mode '
        if perserve_time: command += '--preserve=timestamps '
        command +=  source + ' '  + destination
        print self.name, ': command:', command
        (_, _, stderr) = self.ssh_conn.exec_command(command)
        error_msg = stderr.read()
        if len(error_msg) > 0:
            raise paramiko.ssh_exception.SSHException("Error copying image to local host: " + error_msg)

    def copy_remote_file(self, remote_file, use_incremental):
        ''' Copy a file from the repository to local folder and recursively 
            copy the backing files in case the remote file is incremental
            Read and/or modified self.localinfo['files'] that contain the
            unmodified copies of images in the local path
            params:
                remote_file: path of remote file
                use_incremental: None (leave the decision to this function), True, False
            return:
                local_file: name of local file
                qemu_info: dict with quemu information of local file
                use_incremental_out: True, False; same as use_incremental, but if None a decision is taken
        '''
        
        use_incremental_out = use_incremental
        new_backing_file = None
        local_file = None

        #in case incremental use is not decided, take the decision depending on the image
        #avoid the use of incremental if this image is already incremental
        qemu_remote_info = self.qemu_get_info(remote_file)
        if use_incremental_out==None:
            use_incremental_out = not 'backing file' in qemu_remote_info
        #copy recursivelly the backing files
        if 'backing file' in qemu_remote_info:
            new_backing_file, _, _ = self.copy_remote_file(qemu_remote_info['backing file'], True)
        
        #check if remote file is present locally
        if use_incremental_out and remote_file in self.localinfo['files']:
            local_file = self.localinfo['files'][remote_file]
            local_file_info =  self.get_file_info(local_file)
            remote_file_info = self.get_file_info(remote_file)
            if local_file_info == None:
                local_file = None
            elif local_file_info[4]!=remote_file_info[4] or local_file_info[5]!=remote_file_info[5]:
                #local copy of file not valid because date or size are different. 
                #TODO DELETE local file if this file is not used by any active virtual machine
                try:
                    self.delete_file(local_file)
                    del self.localinfo['files'][remote_file]
                except Exception:
                    pass
                local_file = None
            else: #check that the local file has the same backing file, or there are not backing at all
                qemu_info = self.qemu_get_info(local_file)
                if new_backing_file != qemu_info.get('backing file'):
                    local_file = None
                

        if local_file == None: #copy the file 
            img_name= remote_file.split('/') [-1]
            img_local = self.image_path + '/' + img_name
            local_file = self.get_notused_filename(img_local)
            self.copy_file(remote_file, local_file, use_incremental_out)

            if use_incremental_out:
                self.localinfo['files'][remote_file] = local_file
            if new_backing_file:
                self.qemu_change_backing(local_file, new_backing_file)
            qemu_info = self.qemu_get_info(local_file)
            
        return local_file, qemu_info, use_incremental_out
            
    def launch_server(self, conn, server, rebuild=False, domain=None):
        if self.test:
            time.sleep(random.randint(20,150)) #sleep random timeto be make it a bit more real
            return 0, 'Success'

        server_id = server['uuid']
        paused = server.get('paused','no')
        try:
            if domain!=None and rebuild==False:
                domain.resume()
                #self.server_status[server_id] = 'ACTIVE'
                return 0, 'Success'

            self.db_lock.acquire()
            result, server_data = self.db.get_instance(server_id)
            self.db_lock.release()
            if result <= 0:
                print self.name, ": launch_server ERROR getting server from DB",result, server_data
                return result, server_data
    
        #0: get image metadata
            server_metadata = server.get('metadata', {})
            use_incremental = None
             
            if "use_incremental" in server_metadata:
                use_incremental = False if server_metadata["use_incremental"]=="no" else True

            server_host_files = self.localinfo['server_files'].get( server['uuid'], {})
            if rebuild:
                #delete previous incremental files
                for file_ in server_host_files.values():
                    self.delete_file(file_['source file'] )
                server_host_files={}
    
        #1: obtain aditional devices (disks)
            #Put as first device the main disk
            devices = [  {"type":"disk", "image_id":server['image_id'], "vpci":server_metadata.get('vpci', None) } ] 
            if 'extended' in server_data and server_data['extended']!=None and "devices" in server_data['extended']:
                devices += server_data['extended']['devices']

            for dev in devices:
                if dev['image_id'] == None:
                    continue
                
                self.db_lock.acquire()
                result, content = self.db.get_table(FROM='images', SELECT=('path','metadata'),WHERE={'uuid':dev['image_id']} )
                self.db_lock.release()
                if result <= 0:
                    error_text = "ERROR", result, content, "when getting image", dev['image_id']
                    print self.name, ": launch_server", error_text 
                    return -1, error_text
                if content[0]['metadata'] is not None:
                    dev['metadata'] = json.loads(content[0]['metadata'])
                else:
                    dev['metadata'] = {}
                
                if dev['image_id'] in server_host_files:
                    dev['source file'] = server_host_files[ dev['image_id'] ] ['source file'] #local path
                    dev['file format'] = server_host_files[ dev['image_id'] ] ['file format'] # raw or qcow2
                    continue
                
            #2: copy image to host
                remote_file = content[0]['path']
                use_incremental_image = use_incremental
                if dev['metadata'].get("use_incremental") == "no":
                    use_incremental_image = False
                local_file, qemu_info, use_incremental_image = self.copy_remote_file(remote_file, use_incremental_image)
                
                #create incremental image
                if use_incremental_image:
                    local_file_inc = self.get_notused_filename(local_file, '.inc')
                    command = 'qemu-img create -f qcow2 '+local_file_inc+ ' -o backing_file='+ local_file
                    print 'command:', command
                    (_, _, stderr) = self.ssh_conn.exec_command(command)
                    error_msg = stderr.read()
                    if len(error_msg) > 0:
                        raise paramiko.ssh_exception.SSHException("Error creating incremental file: " + error_msg)
                    local_file = local_file_inc
                    qemu_info = {'file format':'qcow2'}
                
                server_host_files[ dev['image_id'] ] = {'source file': local_file, 'file format': qemu_info['file format']}

                dev['source file'] = local_file 
                dev['file format'] = qemu_info['file format']

            self.localinfo['server_files'][ server['uuid'] ] = server_host_files
            self.localinfo_dirty = True

        #3 Create XML
            result, xml = self.create_xml_server(server_data, devices, server_metadata)  #local_file
            if result <0:
                print self.name, ": create xml server error:", xml
                return -2, xml
            print self.name, ": create xml:", xml
            atribute = libvirt.VIR_DOMAIN_START_PAUSED if paused == "yes" else 0
        #4 Start the domain
            if not rebuild: #ensures that any pending destroying server is done
                self.server_forceoff(True)
            #print self.name, ": launching instance" #, xml
            conn.createXML(xml, atribute)
            #self.server_status[server_id] = 'PAUSED' if paused == "yes" else 'ACTIVE'

            return 0, 'Success'

        except paramiko.ssh_exception.SSHException as e:
            text = e.args[0]
            print self.name, ": launch_server(%s) ssh Exception: %s" %(server_id, text)
            if "SSH session not active" in text:
                self.ssh_connect()
        except libvirt.libvirtError as e:
            text = e.get_error_message()
            print self.name, ": launch_server(%s) libvirt Exception: %s"  %(server_id, text)
        except Exception as e:
            text = str(e)
            print self.name, ": launch_server(%s) Exception: %s"  %(server_id, text)
        return -1, text
    
    def update_servers_status(self):
                            # # virDomainState
                            # VIR_DOMAIN_NOSTATE = 0
                            # VIR_DOMAIN_RUNNING = 1
                            # VIR_DOMAIN_BLOCKED = 2
                            # VIR_DOMAIN_PAUSED = 3
                            # VIR_DOMAIN_SHUTDOWN = 4
                            # VIR_DOMAIN_SHUTOFF = 5
                            # VIR_DOMAIN_CRASHED = 6
                            # VIR_DOMAIN_PMSUSPENDED = 7   #TODO suspended
    
        if self.test or len(self.server_status)==0:
            return            
        
        try:
            conn = libvirt.open("qemu+ssh://"+self.user+"@"+self.host+"/system")
            domains=  conn.listAllDomains() 
            domain_dict={}
            for domain in domains:
                uuid = domain.UUIDString() ;
                libvirt_status = domain.state()
                #print libvirt_status
                if libvirt_status[0] == libvirt.VIR_DOMAIN_RUNNING or libvirt_status[0] == libvirt.VIR_DOMAIN_SHUTDOWN:
                    new_status = "ACTIVE"
                elif libvirt_status[0] == libvirt.VIR_DOMAIN_PAUSED:
                    new_status = "PAUSED"
                elif libvirt_status[0] == libvirt.VIR_DOMAIN_SHUTOFF:
                    new_status = "INACTIVE"
                elif libvirt_status[0] == libvirt.VIR_DOMAIN_CRASHED:
                    new_status = "ERROR"
                else:
                    new_status = None
                domain_dict[uuid] = new_status
            conn.close
        except libvirt.libvirtError as e:
            print self.name, ": get_state() Exception '", e.get_error_message()
            return

        for server_id, current_status in self.server_status.iteritems():
            new_status = None
            if server_id in domain_dict:
                new_status = domain_dict[server_id]
            else:
                new_status = "INACTIVE"
                            
            if new_status == None or new_status == current_status:
                continue
            if new_status == 'INACTIVE' and current_status == 'ERROR':
                continue #keep ERROR status, because obviously this machine is not running
            #change status
            print self.name, ": server ", server_id, "status change from ", current_status, "to", new_status
            STATUS={'progress':100, 'status':new_status}
            if new_status == 'ERROR':
                STATUS['last_error'] = 'machine has crashed'
            self.db_lock.acquire()
            r,_ = self.db.update_rows('instances', STATUS, {'uuid':server_id}, log=False)
            self.db_lock.release()
            if r>=0:
                self.server_status[server_id] = new_status
                        
    def action_on_server(self, req, last_retry=True):
        '''Perform an action on a req
        Attributes:
            req: dictionary that contain:
                server properties: 'uuid','name','tenant_id','status'
                action: 'action'
                host properties: 'user', 'ip_name'
        return (error, text)  
             0: No error. VM is updated to new state,  
            -1: Invalid action, as trying to pause a PAUSED VM
            -2: Error accessing host
            -3: VM nor present
            -4: Error at DB access
            -5: Error while trying to perform action. VM is updated to ERROR
        '''
        server_id = req['uuid']
        conn = None
        new_status = None
        old_status = req['status']
        last_error = None
        
        if self.test:
            if 'terminate' in req['action']:
                new_status = 'deleted'
            elif 'shutoff' in req['action'] or 'shutdown' in req['action'] or 'forceOff' in req['action']:
                if req['status']!='ERROR':
                    time.sleep(5)
                    new_status = 'INACTIVE'
            elif 'start' in req['action']  and req['status']!='ERROR':      new_status = 'ACTIVE'
            elif 'resume' in req['action'] and req['status']!='ERROR' and req['status']!='INACTIVE' :     new_status = 'ACTIVE'
            elif 'pause' in req['action']  and req['status']!='ERROR':      new_status = 'PAUSED'
            elif 'reboot' in req['action'] and req['status']!='ERROR':     new_status = 'ACTIVE'
            elif 'rebuild' in req['action']:
                time.sleep(random.randint(20,150))
                new_status = 'ACTIVE'
            elif 'createImage' in req['action']:
                time.sleep(5)
                self.create_image(None, req)
        else:
            try:
                conn = libvirt.open("qemu+ssh://"+self.user+"@"+self.host+"/system")
                try:
                    dom = conn.lookupByUUIDString(server_id)
                except libvirt.libvirtError as e:
                    text = e.get_error_message()
                    if 'LookupByUUIDString' in text or 'Domain not found' in text or 'No existe un dominio coincidente' in text:
                        dom = None
                    else:
                        print self.name, ": action_on_server(",server_id,") libvirt exception:", text 
                        raise e
                
                if 'forceOff' in req['action']:
                    if dom == None:
                        print self.name, ": action_on_server(",server_id,") domain not running" 
                    else:
                        try:
                            print self.name, ": sending DESTROY to server", server_id 
                            dom.destroy()
                        except Exception as e:
                            if "domain is not running" not in e.get_error_message():
                                print self.name, ": action_on_server(",server_id,") Exception while sending force off:", e.get_error_message()
                                last_error =  'action_on_server Exception while destroy: ' + e.get_error_message()
                                new_status = 'ERROR'
                
                elif 'terminate' in req['action']:
                    if dom == None:
                        print self.name, ": action_on_server(",server_id,") domain not running" 
                        new_status = 'deleted'
                    else:
                        try:
                            if req['action']['terminate'] == 'force':
                                print self.name, ": sending DESTROY to server", server_id 
                                dom.destroy()
                                new_status = 'deleted'
                            else:
                                print self.name, ": sending SHUTDOWN to server", server_id 
                                dom.shutdown()
                                self.pending_terminate_server.append( (time.time()+10,server_id) )
                        except Exception as e:
                            print self.name, ": action_on_server(",server_id,") Exception while destroy:", e.get_error_message() 
                            last_error =  'action_on_server Exception while destroy: ' + e.get_error_message()
                            new_status = 'ERROR'
                            if "domain is not running" in e.get_error_message():
                                try:
                                    dom.undefine()
                                    new_status = 'deleted'
                                except Exception:
                                    print self.name, ": action_on_server(",server_id,") Exception while undefine:", e.get_error_message() 
                                    last_error =  'action_on_server Exception2 while undefine:', e.get_error_message()
                            #Exception: 'virDomainDetachDevice() failed'
                    if new_status=='deleted':
                        if server_id in self.server_status:
                            del self.server_status[server_id]
                        if req['uuid'] in self.localinfo['server_files']:
                            for file_ in self.localinfo['server_files'][ req['uuid'] ].values():
                                try:
                                    self.delete_file(file_['source file'])
                                except Exception:
                                    pass
                            del self.localinfo['server_files'][ req['uuid'] ]
                            self.localinfo_dirty = True

                elif 'shutoff' in req['action'] or 'shutdown' in req['action']:
                    try:
                        if dom == None:
                            print self.name, ": action_on_server(",server_id,") domain not running"
                        else: 
                            dom.shutdown()
#                        new_status = 'INACTIVE'
                        #TODO: check status for changing at database
                    except Exception as e:
                        new_status = 'ERROR'
                        print self.name, ": action_on_server(",server_id,") Exception while shutdown:", e.get_error_message() 
                        last_error =  'action_on_server Exception while shutdown: ' + e.get_error_message()
    
                elif 'rebuild' in req['action']:
                    if dom != None:
                        dom.destroy()
                    r = self.launch_server(conn, req, True, None)
                    if r[0] <0:
                        new_status = 'ERROR'
                        last_error = r[1]
                    else:
                        new_status = 'ACTIVE'
                elif 'start' in req['action']:
                    #La instancia está sólo en la base de datos pero no en la libvirt. es necesario crearla
                    rebuild = True if req['action']['start']=='rebuild'  else False
                    r = self.launch_server(conn, req, rebuild, dom)
                    if r[0] <0:
                        new_status = 'ERROR'
                        last_error = r[1]
                    else:
                        new_status = 'ACTIVE'
                
                elif 'resume' in req['action']:
                    try:
                        if dom == None:
                            pass
                        else:
                            dom.resume()
#                            new_status = 'ACTIVE'
                    except Exception as e:
                        print self.name, ": action_on_server(",server_id,") Exception while resume:", e.get_error_message() 
                    
                elif 'pause' in req['action']:
                    try: 
                        if dom == None:
                            pass
                        else:
                            dom.suspend()
#                            new_status = 'PAUSED'
                    except Exception as e:
                        print self.name, ": action_on_server(",server_id,") Exception while pause:", e.get_error_message() 
    
                elif 'reboot' in req['action']:
                    try: 
                        if dom == None:
                            pass
                        else:
                            dom.reboot()
                        print self.name, ": action_on_server(",server_id,") reboot:" 
                        #new_status = 'ACTIVE'
                    except Exception as e:
                        print self.name, ": action_on_server(",server_id,") Exception while reboot:", e.get_error_message() 
                elif 'createImage' in req['action']:
                    self.create_image(dom, req)
                        
        
                conn.close()    
            except libvirt.libvirtError as e:
                if conn is not None: conn.close
                text = e.get_error_message()
                new_status = "ERROR"
                last_error = text
                print self.name, ": action_on_server(",server_id,") Exception '", text
                if 'LookupByUUIDString' in text or 'Domain not found' in text or 'No existe un dominio coincidente' in text:
                    print self.name, ": action_on_server(",server_id,") Exception removed from host"
        #end of if self.test
        if new_status ==  None:
            return 1

        print self.name, ": action_on_server(",server_id,") new status", new_status, last_error
        UPDATE = {'progress':100, 'status':new_status}
        
        if new_status=='ERROR':
            if not last_retry:  #if there will be another retry do not update database 
                return -1 
            elif 'terminate' in req['action']:
                #PUT a log in the database
                print self.name, ": PANIC deleting server", server_id, last_error
                self.db_lock.acquire()
                self.db.new_row('logs', 
                            {'uuid':server_id, 'tenant_id':req['tenant_id'], 'related':'instances','level':'panic',
                             'description':'PANIC deleting server from host '+self.name+': '+last_error}
                        )
                self.db_lock.release()
                if server_id in self.server_status:
                    del self.server_status[server_id]
                return -1
            else:
                UPDATE['last_error'] = last_error
        if new_status != 'deleted' and (new_status != old_status or new_status == 'ERROR') :
            self.db_lock.acquire()
            self.db.update_rows('instances', UPDATE, {'uuid':server_id}, log=True)
            self.server_status[server_id] = new_status
            self.db_lock.release()
        if new_status == 'ERROR':
            return -1
        return 1
     
    
    def restore_iface(self, name, mac, lib_conn=None):
        ''' make an ifdown, ifup to restore default parameter of na interface
            Params:
                mac: mac address of the interface
                lib_conn: connection to the libvirt, if None a new connection is created
            Return 0,None if ok, -1,text if fails
        ''' 
        conn=None
        ret = 0
        error_text=None
        if self.test:
            print self.name, ": restore_iface '%s' %s" % (name, mac)
            return 0, None
        try:
            if not lib_conn:
                conn = libvirt.open("qemu+ssh://"+self.user+"@"+self.host+"/system")
            else:
                conn = lib_conn
                
            #wait to the pending VM deletion
            #TODO.Revise  self.server_forceoff(True)

            iface = conn.interfaceLookupByMACString(mac)
            iface.destroy()
            iface.create()
            print self.name, ": restore_iface '%s' %s" % (name, mac)
        except libvirt.libvirtError as e:   
            error_text = e.get_error_message()
            print self.name, ": restore_iface '%s' '%s' libvirt exception: %s" %(name, mac, error_text) 
            ret=-1
        finally:
            if lib_conn is None and conn is not None:
                conn.close
        return ret, error_text

        
    def create_image(self,dom, req):
        if self.test:
            if 'path' in req['action']['createImage']:
                file_dst = req['action']['createImage']['path']
            else:
                createImage=req['action']['createImage']
                img_name= createImage['source']['path']
                index=img_name.rfind('/')
                file_dst = self.get_notused_path(img_name[:index+1] + createImage['name'] + '.qcow2')
            image_status='ACTIVE'
        else:
            for retry in (0,1):
                try:
                    server_id = req['uuid']
                    createImage=req['action']['createImage']
                    file_orig = self.localinfo['server_files'][server_id] [ createImage['source']['image_id'] ] ['source file']
                    if 'path' in req['action']['createImage']:
                        file_dst = req['action']['createImage']['path']
                    else:
                        img_name= createImage['source']['path']
                        index=img_name.rfind('/')
                        file_dst = self.get_notused_filename(img_name[:index+1] + createImage['name'] + '.qcow2')
                          
                    self.copy_file(file_orig, file_dst)
                    qemu_info = self.qemu_get_info(file_orig)
                    if 'backing file' in qemu_info:
                        for k,v in self.localinfo['files'].items():
                            if v==qemu_info['backing file']:
                                self.qemu_change_backing(file_dst, k)
                                break
                    image_status='ACTIVE'
                    break
                except paramiko.ssh_exception.SSHException as e:
                    image_status='ERROR'
                    error_text = e.args[0]
                    print self.name, "': create_image(",server_id,") ssh Exception:", error_text
                    if "SSH session not active" in error_text and retry==0:
                        self.ssh_connect()
                except Exception as e:
                    image_status='ERROR'
                    error_text = str(e)
                    print self.name, "': create_image(",server_id,") Exception:", error_text
        
                #TODO insert a last_error at database
        self.db_lock.acquire()
        self.db.update_rows('images', {'status':image_status, 'progress': 100, 'path':file_dst}, 
                {'uuid':req['new_image']['uuid']}, log=True)
        self.db_lock.release()
  
    def edit_iface(self, port_id, old_net, new_net):
        #This action imply remove and insert interface to put proper parameters
        if self.test:
            time.sleep(1)
        else:
        #get iface details
            self.db_lock.acquire()
            r,c = self.db.get_table(FROM='ports as p join resources_port as rp on p.uuid=rp.port_id',
                                    WHERE={'port_id': port_id})
            self.db_lock.release()
            if r<0:
                print self.name, ": edit_iface(",port_id,") DDBB error:", c
                return
            elif r==0:
                print self.name, ": edit_iface(",port_id,") por not found"
                return
            port=c[0]
            if port["model"]!="VF":
                print self.name, ": edit_iface(",port_id,") ERROR model must be VF"
                return
            #create xml detach file
            xml=[]
            self.xml_level = 2
            xml.append("<interface type='hostdev' managed='yes'>")
            xml.append("  <mac address='" +port['mac']+ "'/>")
            xml.append("  <source>"+ self.pci2xml(port['pci'])+"\n  </source>")
            xml.append('</interface>')                

            
            try:
                conn=None
                conn = libvirt.open("qemu+ssh://"+self.user+"@"+self.host+"/system")
                dom = conn.lookupByUUIDString(port["instance_id"])
                if old_net:
                    text="\n".join(xml)
                    print self.name, ": edit_iface detaching SRIOV interface", text
                    dom.detachDeviceFlags(text, flags=libvirt.VIR_DOMAIN_AFFECT_LIVE)
                if new_net:
                    xml[-1] ="  <vlan>   <tag id='" + str(port['vlan']) + "'/>   </vlan>"
                    self.xml_level = 1
                    xml.append(self.pci2xml(port.get('vpci',None)) )
                    xml.append('</interface>')                
                    text="\n".join(xml)
                    print self.name, ": edit_iface attaching SRIOV interface", text
                    dom.attachDeviceFlags(text, flags=libvirt.VIR_DOMAIN_AFFECT_LIVE)
                    
            except libvirt.libvirtError as e:
                text = e.get_error_message()
                print self.name, ": edit_iface(",port["instance_id"],") libvirt exception:", text 
                
            finally:
                if conn is not None: conn.close
                            
                              
def create_server(server, db, db_lock, only_of_ports):
    #print "server"
    #print "server"
    #print server
    #print "server"
    #print "server"
    #try:
#            host_id = server.get('host_id', None)
    extended = server.get('extended', None)
    
#             print '----------------------'
#             print json.dumps(extended, indent=4)
    
    requirements={}
    requirements['numa']={'memory':0, 'proc_req_type': 'threads', 'proc_req_nb':0, 'port_list':[], 'sriov_list':[]}
    requirements['ram'] = server['flavor'].get('ram', 0)
    if requirements['ram']== None:
        requirements['ram'] = 0
    requirements['vcpus'] = server['flavor'].get('vcpus', 0)
    if requirements['vcpus']== None:
        requirements['vcpus'] = 0
    #If extended is not defined get requirements from flavor
    if extended is None:
        #If extended is defined in flavor convert to dictionary and use it
        if 'extended' in server['flavor'] and  server['flavor']['extended'] != None:
            json_acceptable_string = server['flavor']['extended'].replace("'", "\"")
            extended = json.loads(json_acceptable_string)
        else:
            extended = None
    #print json.dumps(extended, indent=4)
    
    #For simplicity only one numa VM are supported in the initial implementation
    if extended != None:
        numas = extended.get('numas', [])
        if len(numas)>1:
            return (-2, "Multi-NUMA VMs are not supported yet")
        #elif len(numas)<1:
        #    return (-1, "At least one numa must be specified")
    
        #a for loop is used in order to be ready to multi-NUMA VMs
        request = []
        for numa in numas:
            numa_req = {}
            numa_req['memory'] = numa.get('memory', 0)
            if 'cores' in numa: 
                numa_req['proc_req_nb'] = numa['cores']                     #number of cores or threads to be reserved
                numa_req['proc_req_type'] = 'cores'                         #indicates whether cores or threads must be reserved
                numa_req['proc_req_list'] = numa.get('cores-id', None)      #list of ids to be assigned to the cores or threads
            elif 'paired-threads' in numa:
                numa_req['proc_req_nb'] = numa['paired-threads']
                numa_req['proc_req_type'] = 'paired-threads'
                numa_req['proc_req_list'] = numa.get('paired-threads-id', None)
            elif 'threads' in numa:
                numa_req['proc_req_nb'] = numa['threads']
                numa_req['proc_req_type'] = 'threads'
                numa_req['proc_req_list'] = numa.get('threads-id', None)
            else:
                numa_req['proc_req_nb'] = 0 # by default
                numa_req['proc_req_type'] = 'threads'

            
            
            #Generate a list of sriov and another for physical interfaces 
            interfaces = numa.get('interfaces', [])
            sriov_list = []
            port_list = []
            for iface in interfaces:
                iface['bandwidth'] = int(iface['bandwidth'])
                if iface['dedicated'][:3]=='yes':
                    port_list.append(iface)
                else:
                    sriov_list.append(iface)
                    
            #Save lists ordered from more restrictive to less bw requirements
            numa_req['sriov_list'] = sorted(sriov_list, key=lambda k: k['bandwidth'], reverse=True)
            numa_req['port_list'] = sorted(port_list, key=lambda k: k['bandwidth'], reverse=True)
            
            
            request.append(numa_req)
                
    #                 print "----------\n"+json.dumps(request[0], indent=4)
    #                 print '----------\n\n'
            
        #Search in db for an appropriate numa for each requested numa
        #at the moment multi-NUMA VMs are not supported
        if len(request)>0:
            requirements['numa'].update(request[0])
    if requirements['numa']['memory']>0:
        requirements['ram']=0  #By the moment I make incompatible ask for both Huge and non huge pages memory
    elif requirements['ram']==0:
        return (-1, "Memory information not set neither at extended field not at ram")
    if requirements['numa']['proc_req_nb']>0:
        requirements['vcpus']=0 #By the moment I make incompatible ask for both Isolated and non isolated cpus
    elif requirements['vcpus']==0:
        return (-1, "Processor information not set neither at extended field not at vcpus")    


    db_lock.acquire()
    result, content = db.get_numas(requirements, server.get('host_id', None), only_of_ports)
    db_lock.release()
    
    if result == -1:
        return (-1, content)
    
    numa_id = content['numa_id']
    host_id = content['host_id']

    #obtain threads_id and calculate pinning
    cpu_pinning = []
    reserved_threads=[]
    if requirements['numa']['proc_req_nb']>0:
        db_lock.acquire()
        result, content = db.get_table(FROM='resources_core', 
                                       SELECT=('id','core_id','thread_id'),
                                       WHERE={'numa_id':numa_id,'instance_id': None, 'status':'ok'} )
        db_lock.release()
        if result <= 0:
            print content
            return -1, content
    
        #convert rows to a dictionary indexed by core_id
        cores_dict = {}
        for row in content:
            if not row['core_id'] in cores_dict:
                cores_dict[row['core_id']] = []
            cores_dict[row['core_id']].append([row['thread_id'],row['id']]) 
           
        #In case full cores are requested 
        paired = 'N'
        if requirements['numa']['proc_req_type'] == 'cores':
            #Get/create the list of the vcpu_ids
            vcpu_id_list = requirements['numa']['proc_req_list']
            if vcpu_id_list == None:
                vcpu_id_list = range(0,int(requirements['numa']['proc_req_nb']))
            
            for threads in cores_dict.itervalues():
                #we need full cores
                if len(threads) != 2:
                    continue
                
                #set pinning for the first thread
                cpu_pinning.append( [ vcpu_id_list.pop(0), threads[0][0], threads[0][1] ] )
                
                #reserve so it is not used the second thread
                reserved_threads.append(threads[1][1])
                
                if len(vcpu_id_list) == 0:
                    break
                
        #In case paired threads are requested
        elif requirements['numa']['proc_req_type'] == 'paired-threads':
            paired = 'Y'
            #Get/create the list of the vcpu_ids
            if requirements['numa']['proc_req_list'] != None:
                vcpu_id_list = []
                for pair in requirements['numa']['proc_req_list']:
                    if len(pair)!=2:
                        return -1, "Field paired-threads-id not properly specified"
                        return
                    vcpu_id_list.append(pair[0])
                    vcpu_id_list.append(pair[1])
            else:
                vcpu_id_list = range(0,2*int(requirements['numa']['proc_req_nb']))
                
            for threads in cores_dict.itervalues():
                #we need full cores
                if len(threads) != 2:
                    continue
                #set pinning for the first thread
                cpu_pinning.append([vcpu_id_list.pop(0), threads[0][0], threads[0][1]])
                
                #set pinning for the second thread
                cpu_pinning.append([vcpu_id_list.pop(0), threads[1][0], threads[1][1]])
                
                if len(vcpu_id_list) == 0:
                    break    
        
        #In case normal threads are requested
        elif requirements['numa']['proc_req_type'] == 'threads':
            #Get/create the list of the vcpu_ids
            vcpu_id_list = requirements['numa']['proc_req_list']
            if vcpu_id_list == None:
                vcpu_id_list = range(0,int(requirements['numa']['proc_req_nb']))
                                
            for threads_index in sorted(cores_dict, key=lambda k: len(cores_dict[k])):
                threads = cores_dict[threads_index]
                #set pinning for the first thread
                cpu_pinning.append([vcpu_id_list.pop(0), threads[0][0], threads[0][1]])
                
                #if exists, set pinning for the second thread
                if len(threads) == 2 and len(vcpu_id_list) != 0:
                    cpu_pinning.append([vcpu_id_list.pop(0), threads[1][0], threads[1][1]])
                
                if len(vcpu_id_list) == 0:
                    break    
    
        #Get the source pci addresses for the selected numa
        used_sriov_ports = []
        for port in requirements['numa']['sriov_list']:
            db_lock.acquire()
            result, content = db.get_table(FROM='resources_port', SELECT=('id', 'pci', 'mac'),WHERE={'numa_id':numa_id,'root_id': port['port_id'], 'port_id': None, 'Mbps_used': 0} )
            db_lock.release()
            if result <= 0:
                print content
                return -1, content
            for row in content:
                if row['id'] in used_sriov_ports or row['id']==port['port_id']:
                    continue
                port['pci'] = row['pci']
                if 'mac_address' not in port: 
                    port['mac_address'] = row['mac']
                del port['mac']
                port['port_id']=row['id']
                port['Mbps_used'] = port['bandwidth']
                used_sriov_ports.append(row['id'])
                break
        
        for port in requirements['numa']['port_list']:
            port['Mbps_used'] = None
            if port['dedicated'] != "yes:sriov":
                port['mac_address'] = port['mac']
                del port['mac']
                continue
            db_lock.acquire()
            result, content = db.get_table(FROM='resources_port', SELECT=('id', 'pci', 'mac', 'Mbps'),WHERE={'numa_id':numa_id,'root_id': port['port_id'], 'port_id': None, 'Mbps_used': 0} )
            db_lock.release()
            if result <= 0:
                print content
                return -1, content
            port['Mbps_used'] = content[0]['Mbps']
            for row in content:
                if row['id'] in used_sriov_ports or row['id']==port['port_id']:
                    continue
                port['pci'] = row['pci']
                if 'mac_address' not in port: 
                    port['mac_address'] = row['mac']  # mac cannot be set to passthrough ports 
                del port['mac']
                port['port_id']=row['id']
                used_sriov_ports.append(row['id'])
                break
    
    #             print '2. Physical ports assignation:'+json.dumps(requirements['port_list'], indent=4)
    #             print '2. SR-IOV assignation:'+json.dumps(requirements['sriov_list'], indent=4)
        
    server['host_id'] = host_id
        

    #Generate dictionary for saving in db the instance resources
    resources = {}
    resources['bridged-ifaces'] = []
    
    numa_dict = {}
    numa_dict['interfaces'] = []
    
    numa_dict['interfaces'] += requirements['numa']['port_list']
    numa_dict['interfaces'] += requirements['numa']['sriov_list']
  
    #Check bridge information
    unified_dataplane_iface=[]
    unified_dataplane_iface += requirements['numa']['port_list']
    unified_dataplane_iface += requirements['numa']['sriov_list']
    
    for control_iface in server.get('networks', []):
        control_iface['net_id']=control_iface.pop('uuid')
        #Get the brifge name
        db_lock.acquire()
        result, content = db.get_table(FROM='nets', SELECT=('name','type', 'vlan'),WHERE={'uuid':control_iface['net_id']} )
        db_lock.release()
        if result < 0: 
            pass
        elif result==0:
            return -1, "Error at field netwoks: Not found any network wit uuid %s" % control_iface['net_id']
        else:
            network=content[0]
            if control_iface.get("type", 'virtual') == 'virtual':
                if network['type']!='bridge_data' and network['type']!='bridge_man':
                    return -1, "Error at field netwoks: network uuid %s for control interface is not of type bridge_man or bridge_data" % control_iface['net_id']
                resources['bridged-ifaces'].append(control_iface)
            else:
                if network['type']!='data' and network['type']!='ptp':
                    return -1, "Error at field netwoks: network uuid %s for dataplane interface is not of type data or ptp" % control_iface['net_id']
                #dataplane interface, look for it in the numa tree and asign this network
                iface_found=False
                for dataplane_iface in numa_dict['interfaces']:
                    if dataplane_iface['name'] == control_iface.get("name"):
                        if (dataplane_iface['dedicated'] == "yes" and control_iface["type"] != "PF") or \
                            (dataplane_iface['dedicated'] == "no" and control_iface["type"] != "VF") or \
                            (dataplane_iface['dedicated'] == "yes:sriov" and control_iface["type"] != "VFnotShared") :
                                return -1, "Error at field netwoks: mismatch at interface '%s' from flavor 'dedicated=%s' and networks 'type=%s'" % \
                                    (control_iface.get("name"), dataplane_iface['dedicated'], control_iface["type"])
                        dataplane_iface['uuid'] = control_iface['net_id']
                        if dataplane_iface['dedicated'] == "no":
                            dataplane_iface['vlan'] = network['vlan']
                        if dataplane_iface['dedicated'] != "yes" and control_iface.get("mac_address"):
                            dataplane_iface['mac_address'] = control_iface.get("mac_address")
                        if control_iface.get("vpci"):
                            dataplane_iface['vpci'] = control_iface.get("vpci")
                        iface_found=True
                        break
                if not iface_found:
                    return -1, "Error at field netwoks: interface name %s from network not found at flavor" % control_iface.get("name")
        
    resources['host_id'] = host_id
    resources['image_id'] = server['image_id']
    resources['flavor_id'] = server['flavor_id']
    resources['tenant_id'] = server['tenant_id']
    resources['ram'] = requirements['ram']
    resources['vcpus'] = requirements['vcpus']
    resources['status'] = 'CREATING'
    
    if 'description' in server: resources['description'] = server['description']
    if 'name' in server: resources['name'] = server['name']
    
    resources['extended'] = {}                          #optional
    resources['extended']['numas'] = []
    numa_dict['numa_id'] = numa_id
    numa_dict['memory'] = requirements['numa']['memory']
    numa_dict['cores'] = []

    for core in cpu_pinning:
        numa_dict['cores'].append({'id': core[2], 'vthread': core[0], 'paired': paired})
    for core in reserved_threads:
        numa_dict['cores'].append({'id': core})
    resources['extended']['numas'].append(numa_dict)
    if extended!=None and 'devices' in extended:   #TODO allow extra devices without numa
        resources['extended']['devices'] = extended['devices']
    

    print '===================================={'
    print json.dumps(resources, indent=4)
    print '====================================}'
    
    return 0, resources