linuxwebcluster.com

A customer installed RenderFarmer on their server and tried to use eth1 as the interface to communicate with render nodes... But only the use of eth0 is supported. So how do we change it? I'll post the support ticket here for anyone with a similar issue:

Customer:    Hello, I did a vanilla CentOS 5.2 install, installed all updates, and ran the RenderFarmer installer. eth0 receives a IP from [our University's]  DHCP servers. After running your installer, the virtual interface eth0:0 was created with 10.1.1.1. However, our render farm nodes are connected via a switch and cable connected to eth1. We took a look at our logs and the render farm master is serving DHCP addresses to the University network on eth0. What we need to be able to do is get 10.1.1.1 over to eth1 so the render farm nodes are isolated and we're no longer attempting to assign DHCP addresses to machines on the University side of the network (eth0).

Support:   Basically we just need to switch the IP's. The cluster will use eth0, period. So if you switch cables and make eth1 DHCP from University network, and make eth0 10.1.1.1 you will be all set. You should then edit /cluster/mon/mon_common and /cluster/bin/lvs-init and set a new virtual IP there... Something on the 10.1.1.x range. Doesn't matter what since you guys may never use that functionality anyway. Just remember that if you assign 10.1.1.250, say, that you don't also assign that to a render node.

You will also have to do 'service ipvsadm stop' first... That will get rid of eth0:0 until next boot or until the service is manually restarted. Until the IP is down, you won't be able to assign it to another interface. Also, the settings for DrQueue will need to be updated. If you look in /etc/profile you'll see where:
DRQUEUE_MASTER=OLD_IP and and again in /etc/init.d/drq-slave, which will have a similar line.

Other places the IP will need to be changed....  

/cluster/cluster_nodes
/etc/glusterfs/gluster-server.vol (change the IP range to 10.1.1.x)
/etc/glusterfs/gluster-client.vol
/etc/hosts
/etc/dhcpd.conf