How to configure multiple IP-Adresses on one NIC in OVM

Question

Hi guys,
we have some OVM Servers 2.2.1 installed. They all have three NICs in them (eth0-2). For eth0 and eth2 we need multiple IP-Adresses configured to work with our storage solution. The configuration should look like this:
eth0:0 - 192.168.31.x
eth0:1 - 192.168.33.x
eth1 - 192.168.0.x
eth2:0 - 192.168.32.x
eth2:1 - 192.168.34.x
I tried creating gonfig files ifcfg-eth0:0 in /etc/sysconfig/network-scripts with the following content
DEVICE=eth0:0
BOOTPROTO=static
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=192.168.31.3
TYPE=Ethernet
HWADDR=00:1b:21:06:f0:fa
But it does not work. Neither eth0:0 nore an additional xenbr is configured when i restart.
I can configure multiple ip addresses for xenbr0 by calling something like "ifconfig xenbr0 192.168.31.x". But these settings get lost as sonn as i reboot the server.
I have already searched google, forums and blogs for a solution but could not find one. I thought that this should be a pretty common task. In "normal" linux it is not an issue at all.
Has somebody any experience with a setup like this? I would really apreciate your help.
Thanks
Marek

Answer 1

Hi,
configuring IP aliasses seems to work the same way like configuring VLANs. You will have to configure the appropriate bridges at system startup manually.
E.g. this little script is what I use to configure VLANs and briges on my OVM:
#!/bin/bash
echo "Configuring VLANs and bridges\n"
echo "Configuring VLAN 24 on eth2"
vconfig add eth2 24
brctl addbr br2.24
brctl addif br2.24 eth2.24
ifconfig eth2.24 up
ifconfig br2.24 up
echo "Configuring VLAN 31 on eth2"
vconfig add eth2 31
brctl addbr br2.31
brctl addif br2.31 eth2.31
ifconfig eth2.31 up
ifconfig br2.31 up
This script is run at startup by init using this startup skript in /etc/init.d, which is what I think you're missing as you can already seem to bring up the needed IPs manually - you'd have to change the chkconfig accordingly, that is make sure that the config script gets startet after the network has been brought up, like this: # chkconfig: 2345 11 91
[root@oraclevm01 ~]# cat /etc/init.d/vlan-config
#! /bin/bash
# vlan-config configure VLANs
# chkconfig: 2345 11 89
# description: Configures VLANs at boot time before the \
# network is started.
### BEGIN INIT INFO
# Provides: $vlan
### END INIT INFO
# Source function library.
. /etc/init.d/functions
if [ ! -f /etc/vlan-config ]; then
exit 0
fi
# See how we were called.
case $1 in
     start)
               # configure vlans
               /etc/vlan-config
          echo $"Usage: $0 {start}"
          exit 1
esac
exit 0
Hth,
budy
Edited by: budachst on Jun 29, 2011 8:11 AM