[Linux-cluster] RHCS

[Gordan Bobic]

Sreeharsha Totakura wrote:
> Hi,
> 
> I am using RHCS 5.2 for achieving High Availability in MySQL database
> service. I have configured two nodes; one as a primary and the other as a
> backup. Both the servers have GFS on SAN.
> 
> The cluster suite is configured properly and when a node shuts down, the
> service is being started in the other node with the configured virtual ip
> address for MySQL service. However, if we plug out the network link to the
> primary server the service is not being started in the other node; even
> after having 'monitor_link="1"' in cluster.conf for that virtual ip
> address.
> 
> Our servers are connected by redundant SAN connections so we have 6 network
> interfaces on both the servers. I feel the nodes are still able to
> communicate through these network connections which are being used for SAN
> volumes. Is there anyway in which I can configure cluster manager to bind
> the virtual ip for MySQL service to an interface and monitor the link on
> that interface?

The virtual IP will always be assigned to the interface with the static 
IP on the same subnet.

i.e. if you have an interface eth0 on 10.1.1.1/24, and the floating IP 
is 10.1.1.2, it'll automatically go to the eth0 interface. Is this not 
what is happening in your setup? I think link monitoring should be on 
the static, rather than floating IP resource (that's what I do, and it 
works for me).

Gordan