Dear All,

We have setup a High Available Cluster on two RHEL 5.4 machines with Redhat Cluster Suite (RHCS) having following configuration.

1. Both machines have Mysql server, Apache web server and Zabbix server.
2. Mysql database and web pages reside in SAN.
3. Active machine holds virtual IP and mounted shared disk.
4. We have also included a script in RHCS which takes care of starting Mysql, Apache and zabbix server on the machine which turns active when cluster switches over.

The above configuration holds good if Active machine goes down as a result of hardware failure or Reboot.

What if, If any one service say Apache/Mysql/zabbix running on active hangs or become unresponsive.

How can we handle this scenario ? Please advice.

Warm Regards,

It's difficult to say. Could you give us some more information about what type of SAN you are using and how it is configured. That is: SAN network layout, Disk layout, How is the data distributed over the disks.

Otherwise I have to guess and my conclusion would be not possible.
Reason for this: If System A has to run Apache/zabbix and System B Mysql in a failover situation they need both access to the same disks on the SAN. Which is not possible in normal failover configurations. Unless you got special software that allows this.

Besides I didn't know that configuring and maintaining HA clusters is a newbie job nowadays.

_______________
Gerrard

Hi gdejonge,

Thanks for your reply.

At any point of time /shared_disk is mounted on active machine. So we are trying to achive Failover in such a way at any point of time Apache, Mysql and Zabbix should be running on a single server.

Following scenairo is not allowed:

The direction is given by people who are managing SAN.

ServerA: Mysql and zabbix
ServerB: Apache

The above scenario is not allowed.

So we need to switch over all the services running on serverA to serverB, If any one of the services fails in serverB.

Our current configuration switches over all the services only in case of reboot. Is there any way to implement this service switchover from RHCS.

Thanks

Okay I understand it now.
You not only want hardware failover, but also service failover.
Conform the RHCS advertisements this should be possible.
You probably need to do some reading in the RHCS manuals, about how to configure the service failover.

_________________
Gerrard