Pacemaker

From Linux-HA

In order to be useful to users, the Heartbeat daemon needs to be combined with a cluster resource manager (CRM) which has the task of starting and stopping the services (IP addresses, web servers, etc) that cluster will make highly available.

Heartbeat originally came with a primitive resource manager, however this is only capable of managing 2 nodes and could not detect resource-level failures.

A new resource manager which addressed these limitations and more was written for Heartbeat 2.0.0.

In 2007 the new resource manager was spun-off to become in order to better support additional cluster stacks (such as OpenAIS/Corosync).

Information about Pacemaker is available from the project web site.

There are various user interfaces to Pacemaker:

• the crm shell by Dejan Muhamedagic, a powerful commandline/curses interface hiding the xml configuration details, including online help and tab completion
• the high availability web konsole by Tim Serong, an AJAX web frontent in its very early stages
• the heartbeat gui by Yan Gao, basically an advanced xml editor plus action buttons and status display
• the DRBD-MC by Rasto Levrinc of LINBIT, a Java based platform independent management console , featuring various wizards and even integrating a VNC Viewer for Virtual Machines controlled by Pacemaker.