I'm creating a 2+1 failover cluster under Red Hat 5.5 with 4 services of which 2 have to run on the same node, sharing the same virtual IP address. One of the services on each node needs a (SAN) disk, the other doesn't. I'm using HA-LVM. When I shut down (via ifdown) the two interfaces connected to the SAN to simulate SAN failure, the service needing the disk is disabled, the other keeps running, as expected. Surprisingly (and unfortunately), the virtual IP address shared by the two services on the same machine is also removed, rendering the still-running service useless. How can I configure the cluster to keep the IP address up?