The Heartbeat program should be running on both nodes. Check this by running /etc/init.d/heartbeat status on both nodes.

[root@tlha-primary conf.d]# /etc/init.d/heartbeat status
heartbeat OK [pid 3665 et al] is running on tlha-primary.example.com...

[root@tlha-secondary conf.d]# /etc/init.d/heartbeat status
heartbeat OK [pid 3675 et al] is running on tlha-secondary.example.com...

The pid of the heartbeat process will of course differ compared to the example above.

When Heartbeat is running on either machine, it should be possible to ping the HA interface from both cluster nodes, from the VSM agent machines and from the rest of the network. It should also be possible to connect to the HA interface using the ThinLinc client from any host on the network. The HA interface is active only on the currently active node, as a virtual interface (typically eth0:1). Verify this by using the ifconfig command. Example output:

[root@tlha-primary root]# ifconfig -a
eth0      Link encap:Ethernet  HWaddr 00:80:C8:E0:8C:5C  
          inet addr:10.0.0.2  Bcast:10.47.0.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:587769 errors:1 dropped:0 overruns:0 frame:0
          TX packets:286618 errors:6 dropped:0 overruns:0 carrier:6
          collisions:0 txqueuelen:100 
          RX bytes:69064645 (65.8 Mb)  TX bytes:42452764 (40.4 Mb)
          Interrupt:12 Base address:0x7000 

eth0:0    Link encap:Ethernet  HWaddr 00:80:C8:E0:8C:5C  
          inet addr:10.0.0.4  Bcast:10.0.0.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:587769 errors:1 dropped:0 overruns:0 frame:0
          TX packets:286618 errors:6 dropped:0 overruns:0 carrier:6
          collisions:0 txqueuelen:100 
          RX bytes:69064645 (65.8 Mb)  TX bytes:42452764 (40.4 Mb)
          Interrupt:12 Base address:0x7000 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:136 errors:0 dropped:0 overruns:0 frame:0
          TX packets:136 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:25016 (24.4 Kb)  TX bytes:25016 (24.4 Kb)

The output above is from our example setup where the primary node has IP address 10.0.0.2 and the HA interface is 10.0.0.4. The output is from an occasion where the primary node is the active node.

As a summary of the validation steps earlier in this section, we'll now describe how an active node can be recognized and validated.