Hello All Linux Experts,

I have setup a MySQL High Availability Cluster with two nodes using DRBD & Heartbeat. I have successfully installed the cluster but one question which is still not solved is that Heartbeat monitors failover of network or server failure, etc.

What will happen if MySQL service gets stopped or do not start. This heartbeat-DRBD cluster does not take any action on that part.

Now I want to enable this feature too which also monitors MySQL service. I have gone through MON help on web but could not find out any good step by step tutorial.

Please help me.............

If I am not wrong, heartbeat is not monitor the service (MySQL). Heartbeat will only check the two physical servers. If primary go down, all the services at primary will take over by slave. ( check via control channel - whatever you configure at /etc/ha.d/ha.cf )
Since your data (data files of mysql /var/lib/mysql) is put it on DRBD, your redundant data is identical.
But let say your Mysql database has load issue, heartbeat will not take care about that.

Thanks for the reply. Yes Heartbeat monitors the two physical servers for network outage, power failure, etc. It doesn't care about the services running on the two servers. Apart from the failover of any server there are chances that sometimes a service may fail too. I also want to have the high availability of MySQL service. In any case if MySQL service gets down the other server should switch on its MySQL service & start serving the users requests on the virtual IP which is taken from the other server.

Regds
Sushant Chawla

Heartbeat will only check the two physical servers. If primary go down, all the services at primary will take over by slave.

Yes I know, that's why I am asking for high availability solution which can give me high availability for services on the server too.

Regds
Sushant Chawla

You can use MySQL Cluster feature. That will be the HA and Load balance.

I could've used MySQL cluster but currently it doesn't support InnoDB tables, that's why I am looking for alternatives.

Regds
Sushant Chawla

In this case, you may want you use combination of HA, DRBD and monit.
monit is monitoring daemon of services. You can monitor MySQL and send email alert, trigger certain behavior like restart MySQL server.

Thanks a lot for this good suggestion. I visited Monit website & it looks like we can configure it in our scenario. I am searching for a direct documentation for MySQL with Monit, do you know any direct link for my requirement??

Regds
Sushant Chawla

For Monit setup
http://www.howtoforge.net/server-mon...andriva-2010.0

You can also try with popular project mon. It is also very popular project.
http://www.oreillynet.com/pub/a/data...er.html?page=3

Cheer

Yeah the docs look good. I will surely give both a try. Thanks again for the suggestions, I will update you with the results soon.

Regds
Sushant Chawla

sushantchawla2005,
We have a similar setup with DRBD and Heartbeat but no service monitoring service. I've been looking at the monit recently but haven't had a chance to implement it in our production environment. I'm looking forward to what you find out.