Document SDN Assist test

magma/README.md

@@ -119,6 +119,38 @@ VIM-level metrics are being collected by default, they can be observed at the Gr
 
 Magma AGW VDU is configured for autoscaling when CPU exceeds a threshold. After scaling, services are not automatically balanced (possible add-on for future hackfests)
 
-## Pending additions
+### SDN Assist
 
-- SDN Assist in the internal S1 VLD (Bug 1082)
\ No newline at end of file
+The MagmaAGW+srsLTE VNF has been designed so that there can be an SDN-Assisted data-plane in the internal S1 VLD. As long as the interfaces are declared as "SR-IOV" in the descriptor, instead of PARAVIRT/VIRTIO.
+
+Even though it can be tested with any fabric for which there is an SDN Assist plugin in OSM, this documentation will refer to the case where an OpenFlow-based fabric is used to interconnect the servers, so that ONOS VPLS becomes the ideal plugin to use.
+
+Requirements:
+- Each server where an AGW or srsLTE VDU is expected to be launched should have an SR-IOV-enabled port towards the OpenFlow fabric.
+- The VIM must have been created with a reference to the physnet(s) to use for SR-IOV (typically something like: `--config '{dataplane_physical_net: physnet2, microversion: 2.32}'`)
+- An ONOS SDN Controller must be installed and it must be reachable from OSM, for example, you can use the following snippet inside the OSM VM:
+```
+docker run -t -d --restart always --network host --name onos onosproject/onos
+
+docker exec -it onos /bin/bash
+apt update
+apt install -y openssh-server
+
+ssh -p 8101 -o StrictHostKeyChecking=no karaf@localhost
+
+# These entries may require a ctrl+c to escape back to prompt, or rather use the ONOS GUI. 
+onos:app activate org.onosproject.openflow-base
+onos:app activate org.onosproject.openflow
+onos:app activate org.onosproject.ofagent
+onos:app activate org.onosproject.vpls
+
+``` 
+- An "SDN Port Mapping" file must be prepared to include all the possible PCI ports that can be selected by the VIM, per port. An example for ETSI VIM is included in this repo.
+- The VIM user must have admin privileges.
+
+Procedure:
+1. Create the SDN Controller in OSM, for example:
+`osm sdnc-create --name onos01 --type onos_vpls --url http://172.21.248.19:8181 --user karaf --password karaf`
+1. Update the VIM to use the SDN Controller and the port mapping file, for example:
+`osm vim-update etsi-openstack --sdn_controller onos01 --sdn_port_mapping sdn_port_mapping.yaml`
+1. Instantiate with SR-IOV ports. OpenFlow entries will be created and can be seen at the ONOS GUI (http://onos_ip/onos/ui)