fix bug 1483: read only the IP address of the right device with the default route

Change-Id: I84a239ad062d00abc993fbab9f090f1c0a2b2a19
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>

installers/full_install_osm.sh

@@ -137,7 +137,7 @@ function remove_iptables() {
 
     if [ -z "$DEFAULT_IP" ]; then
         DEFAULT_IF=$(ip route list|awk '$1=="default" {print $5; exit}')
-        [ -z "$DEFAULT_IF" ] && DEFAULT_IF=$(route -n |awk '$1~/^0.0.0.0/ {print $8; exit}')
+        [ -z "$DEFAULT_IF" ] && DEFAULT_IF=$(ip route list|awk '$1=="default" {print $5; exit}')
         [ -z "$DEFAULT_IF" ] && FATAL "Not possible to determine the interface with the default route 0.0.0.0"
         DEFAULT_IP=`ip -o -4 a |grep ${DEFAULT_IF}|awk '{split($4,a,"/"); print a[1]}'`
         [ -z "$DEFAULT_IP" ] && FATAL "Not possible to determine the IP address of the interface with the default route"
@@ -1199,7 +1199,7 @@ function install_lightweight() {
     DEFAULT_IF=$(ip route list|awk '$1=="default" {print $5; exit}')
     [ -z "$DEFAULT_IF" ] && DEFAULT_IF=$(route -n |awk '$1~/^0.0.0.0/ {print $8; exit}')
     [ -z "$DEFAULT_IF" ] && FATAL "Not possible to determine the interface with the default route 0.0.0.0"
-    DEFAULT_IP=`ip -o -4 a |grep ${DEFAULT_IF} |awk '{split($4,a,"/"); print a[1]}'`
+    DEFAULT_IP=`ip -o -4 a s ${DEFAULT_IF} |awk '{split($4,a,"/"); print a[1]}'`
     [ -z "$DEFAULT_IP" ] && FATAL "Not possible to determine the IP address of the interface with the default route"
     DEFAULT_MTU=$(ip addr show ${DEFAULT_IF} | perl -ne 'if (/mtu\s(\d+)/) {print $1;}')