What is external inetrface of network node?
Iam very new to openstack. I succesffully tried Openstack-Devstack instalation on single node. Now i started minimal architecture with neutron netwokring with compute node, controller node and netwrok node. I dont understand what is 3rd NIC of Network Node doing. What is the purpose of interface without any IP?? My OS is ubuntu 14.04 LTS. My 3rd NIC of Network Node is eth3. I edited /etc/network/interfaces as given in the Openstack documentation. After reeboot eht3 is updated without any IP. is that needed?? Any tests needed to perfom to check whether I have done correct configuartion for eth3?? please help...
my /etc/network/interfaces is
auto lo
iface lo inet loopback
allow-hotplug eth1
auto eth1
iface eth1 inet static
address 192.168.9.10
netmask 255.255.255.0
gateway 192.168.9.254
dns-nameservers 8.8.8.8
allow-hotplug eth2
auto eth2
iface eth2 inet static
address 10.0.1.21
netmask 255.255.255.0
auto eth3
allow-hotplug eth3
iface eth3 inet manual
up ip link set dev $IFACE up
down ip link set dev $IFACE down