Using DRBD in Heartbeat R1-style clusters-Ro の博客

mrbear

This resource configuration contains one resource group whose home node (the node where its resources are expected to run under normal circumstances) is named bob. Consequentially, this resource group would be considered the local resource group on host bob, whereas it would be the foreign resource group on its peer host.　　The resource group includes a DRBD resource named mysql, which will be promoted to the primary role by the cluster manager (specifically, the drbddisk resource agent) on whichever node is currently the active node. Of course, a corresponding resource must exist and be configured in /etc/drbd.conf for this to work.
　　That DRBD resource translates to the block device named /dev/drbd0, which contains an ext3 filesystem that is to be mounted at /var/lib/mysql (the default location for MySQL data files).
　　The resource group also contains a service IP address, 10.9.42.1. Heartbeat will make sure that this IP address is configured and available on whichever node is currently active.
　　Finally, Heartbeat will use the LSB resource agent named mysql in order to start the MySQL daemon, which will then find its data files at /var/lib/mysql and be able to listen on the service IP address, 192.168.42.1.
　　It is important to understand that the resources listed in the haresources file are always evaluated from left to right when resources are being started, and from right to left when they are being stopped.