Synchronizing Sysctl; Synchronizing Network Packet Filtering Rules; Starting Lvs - Red Hat ENTERPRISE LINUX 5 - VIRTUAL SERVER ADMINISTRATION Manual

Important
To use scp the sshd must be running on the backup router, see
Services on the LVS Routers"
services on the LVS routers.
Issue the following command as the root user from the primary LVS router to sync the lvs.cf files
between the router nodes:
scp /etc/sysconfig/ha/lvs.cf n.n.n.n:/etc/sysconfig/ha/lvs.cf
In the command, replace n.n.n.n with the real IP address of the backup LVS router.

4.7.2. Synchronizing sysctl

The sysctl file is only modified once in most situations. This file is read at boot time and tells the
kernel to turn on packet forwarding.
Important
If you are not sure whether or not packet forwarding is enabled in the kernel, see
Section 2.5, "Turning on Packet Forwarding"
necessary, enable this key functionality.

4.7.3. Synchronizing Network Packet Filtering Rules

If you are using iptables, you will need to synchronize the appropriate configuration file on the
backup LVS router.
If you alter the any network packet filter rules, enter the following command as root from the primary
LVS router:
scp /etc/sysconfig/iptables n.n.n.n:/etc/sysconfig/
In the command, replace n.n.n.n with the real IP address of the backup LVS router.
Next either open an ssh session to the backup router or log into the machine as root and type the
following command:
/sbin/service iptables restart
Once you have copied these files over to the backup router and started the appropriate services (see
Section 2.1, "Configuring Services on the LVS Routers"
LVS.

4.8. Starting LVS

To start LVS, it is best to have two root terminals open simultaneously or two simultaneous root open
ssh sessions to the primary LVS router.
In one terminal, watch the kernel log messages with the command:
for details on how to properly configure the necessary
for instructions on how to check and, if
for more on this topic) you are ready to start
Synchronizing sysctl
Section 2.1, "Configuring
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