Failover to Standby and restart Primary Pre CMI How To

Overview

This article explains how to failover the Virtual IP (VIP) to the Standby server for a pair of Active/Active appliances and has primarily been written to supplement other articles that might require these steps to be performed.

Aside from the actual process of failing over the VIP, it also details some status checks which can be performed on the command line to check that the VIP has gone across. It then explains how to restart Tomcat on the Primary server.

If your appliances have the CMI menu system then please see: Failover to Standby and restart Primary How To.

Check Heartbeat status on Standby

• Login via SSH to the Standby using the PuTTY How To Guide;

• Check the status of Heartbeat using the following command:
  • service heartbeat status

If Heartbeat has a status of Running on the Standby, you can be confident that when you stop Heartbeat on the Primary it will failover the VIP to the Standby. If it doesn't, then check to see if Heartbeat is running on the Primary. If it isn't running on either machine then it's probable that you aren't even using the VIP.

Stop Heartbeat on Primary:

• This should take up to 30 seconds or so to failover;

• Login via SSH to the Primary using the PuTTY How To Guide;

• Stop Heartbeat using the following command:
  • service heartbeat stop

Verify that the VIP has gone across to the Standby

There are a few ways this can be verified...

• Access the PINsafe Administration Console via web browser using the VIP. You should notice that the server name at the top right hand corner is now that of the Standby server;

• From the command line enter the following command:
  • ifconfig
  • You should observe that the Standby has a network interface entry labelled eth0:0 in addition to eth0, eth1 and lo. eth0:0 is the VIP. Perform the same check on the Primary to ensure that this no longer exists when you perform the ifconfig command there;
  • To exit from the command line type the exit command and press enter.

Validate the failover has been successful

• Attempt to login to access devices that PINsafe has been integrated with;

If all is well proceed to restart Tomcat on the Primary:

• Login via SSH to the Primary using the following article PuTTY How To Guide;
• Restart Tomcat using the following command:
  • service tomcat5 restart

If Tomcat restarts successfully, proceed to start Heartbeat on the Primary to initiate the failback.

Start Heartbeat on Primary

• This should take up to 30 seconds or so to failback;
• Login via SSH to the Primary using the PuTTY How To Guide;
• Start Heartbeat using the following command:
  • service heartbeat start

Verify that the VIP has gone back to the Primary

There are a few ways this can be verified...

• Access the PINsafe Administration Console via web browser using the VIP. You should notice that the server name at the top right hand corner is now that of the Primary server;

• From the command line enter the following command:
  • ifconfig
  • You should observe that the Primary has a network interface entry labelled eth0:0 in addition to eth0, eth1 and lo. eth0:0 is the VIP. Perform the same check on the Standby to ensure that this no longer exists when you perform the ifconfig command there;
  • To exit from the command line type the exit command and press enter.

Validate the failback has been successful

• Attempt to login to access devices that PINsafe has been integrated with;