Troubleshooting Linux HA (High Availability)

25 Feb 2009

When Linux HA (High Availability) is setup, each machine will have a physical address, and one machine should also have the virtual address.

This can be checked via ip addr:

machine 1
2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:09:3d:12:af:77 brd ff:ff:ff:ff:ff:ff
    inet 999.99.133.12/23 brd 211.29.133.255 scope global eth0

machine 2
2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:09:3d:12:ba:ef brd ff:ff:ff:ff:ff:ff
    inet 999.99.133.13/23 brd 211.29.133.255 scope global eth0
    inet 999.99.133.19/23 brd 211.29.133.255 scope global secondary eth0:1

If this isn’t the case, do a hb_takeover on the appropriate machine (depending on the status of the underlying application). Eg /usr/lib64/heartbeat/hb_takeover