Getting Started with Heartbeat

 in
Your first step toward high-availability bliss.
Troubleshooting

Now that your cluster is all configured, start it with:

/etc/init.d/heartbeat start

Things might work perfectly or not at all. Fortunately, with logging enabled, troubleshooting is easy, because Heartbeat outputs informative log messages. Heartbeat even will let you know when a previous log message is not something you have to worry about. When bringing a new cluster on-line, I usually open an SSH terminal to each cluster member and tail the messages file like so:

tail -f /var/log/messages

Then, in separate terminals, I start up Heartbeat. If there are any problems, it is usually pretty easy to spot them.

Heartbeat also comes with very good documentation. Whenever I run into problems, this documentation has been invaluable. On my system, it is located under the /usr/share/doc/ directory.

Conclusion

I've barely scratched the surface of Heartbeat's capabilities here. Fortunately, a lot of resources exist to help you learn about Heartbeat's more-advanced features. These include active/passive and active/active clusters with N number of nodes, DRBD, the Cluster Resource Manager and more. Now that your feet are wet, hopefully you won't be quite as intimidated as I was when I first started learning about Heartbeat. Be careful though, or you might end up like me and want to cluster everything.

Daniel Bartholomew has been using computers since the early 1980s when his parents purchased an Apple IIe. After stints on Mac and Windows machines, he discovered Linux in 1996 and has been using various distributions ever since. He lives with his wife and children in North Carolina.

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2 Nodes configured, unknown expected votes

Anonymous's picture

Hi, this article is easy to configure heartbeat.

my monitoring command showing
============
Last updated: Wed Mar 17 18:44:42 2010
Stack: Heartbeat
Current DC: node1 (e9de9b67-cebf-4dd6-aeab-0276b49320ed) - partition with quorum
Version: 1.0.5-3840e6b5a305ccb803d29b468556739e75532d56
2 Nodes configured, unknown expected votes
0 Resources configured.
============

Online: [ node2 node1 ]

Why am getting "unknown expected votes"

Thanks
Jonam

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