Getting Started with Heartbeat
Now that your cluster is all configured, start it with:
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.
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.
The High-Availability Linux Project: www.linux-ha.org
Heartbeat Home Page: www.linux-ha.org/Heartbeat
Getting Started with Heartbeat Version 2: www.linux-ha.org/GettingStartedV2
An Introductory Heartbeat Screencast: linux-ha.org/Education/Newbie/InstallHeartbeatScreencast
The Linux-HA Mailing List: lists.linux-ha.org/mailman/listinfo/linux-ha
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.
August 27, 2015
12:00 PM CDT
Free to Linux Journal readers.Register Now!
- Three More Lessons
- Django Models and Migrations
- August 2015 Issue of Linux Journal: Programming
- Hacking a Safe with Bash
- The Controversy Behind Canonical's Intellectual Property Policy
- Secure Server Deployments in Hostile Territory, Part II
- Shashlik - a Tasty New Android Simulator
- Huge Package Overhaul for Debian and Ubuntu
- Embed Linux in Monitoring and Control Systems
- KDE Reveals Plasma Mobile