FAS2720 & AFF220 4 Node cluster

Hi,

We are having an issue where we have following setup:

- we have 4 nodes cluster with different IPs say X.X.X.1 to X.X.X.4

- we have 1 Cluster management LIF x.x.x.5

 

Now the issue is that when we unplug the management cable from X.X.X.1 the other node do not take over automatically the cluster management LIF IP (cluster management IP not accessible) and we have to manually shift it to other node. Please guide us what we are missing in this situation.   

Thanks.