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4.7. Synchronizing Configuration Files

After configuring the primary LVS router, there are several configuration files that must be copied to the backup LVS router before you start the Load Balancer Add-On.
These files include:
  • /etc/sysconfig/ha/ — the configuration file for the LVS routers.
  • /etc/sysctl — the configuration file that, among other things, turns on packet forwarding in the kernel.
  • /etc/sysconfig/iptables — If you are using firewall marks, you should synchronize one of these files based on which network packet filter you are using.


The /etc/sysctl.conf and /etc/sysconfig/iptables files do not change when you configure the Load Balancer Add-On using the Piranha Configuration Tool.

4.7.1. Synchronizing

Anytime the LVS configuration file, /etc/sysconfig/ha/, is created or updated, you must copy it to the backup LVS router node.


Both the active and backup LVS router nodes must have identical files. Mismatched LVS configuration files between the LVS router nodes can prevent failover.
The best way to do this is to use the scp command.


To use scp the sshd must be running on the backup router, see Section 2.1, “Configuring Services on the LVS Router” for details on how to properly configure the necessary services on the LVS routers.
Issue the following command as the root user from the primary LVS router to sync the files between the router nodes:
scp /etc/sysconfig/ha/ n.n.n.n:/etc/sysconfig/ha/
In the command, replace n.n.n.n with the real IP address of the backup LVS router.