Tuesday, November 17, 2015

CDOT Tips: InterCluster LIFs

When you see ICL or “InterCluster LIF,” think SnapMirror/SnapVault.  ICL’s are interfaces totally dedicated to replication between clusters, that’s all they can do.  Here’s a couple important things to think about:

1.       There are two kinds of replication in CDOT:
a.       IntraCluster: this means volume move from one node to the other within the cluster.  This occurs using SnapMirror via the private 10Gb cluster network.
b.      InterCluster: This means SnapMirror or SnapVault to another cluster, which occurs over TR’s shared network.
2.     All of a cluster’s SnapMirror and SnapVault to other clusters only occur via the ICL’s. 
3.       ICLs work on two kinds of ports: Role=Data or Role=InterCluster.  Remember, you can assign a role to a port so that only LIFs with compatible roles will ever land there.

4.       Create at least 1 ICL per node.  ICL’s can’t be failed over between nodes, they are dedicated to that node.

5.       In 8.2, a node’s ICL’s can only be in a single network.   In 8.3 IPSpaces are re-introduced and allow multiple ICL’s in multiple IPSpaces per node.