In the blog post Converged Perfstat and Clustered ONTAP, I discussed how to use the Converged Perfstat tool to collect performance data and stats on an ONTAP cluster. By default, a command line such as
Perfstat8 <cluster IP addr> –-mode=c
will collect data on all nodes within the cluster. Suppose the cluster has N nodes and you are only interested in two nodes: i,j (where i < N; j <= N), What should you do?
You can use the ‘–-nodes’ command line switch to specify the nodes of interest as follows:
Perfstat8 <cluster IP addr> --nodes=<nodei IP>,<nodej IP> –-mode=c
This way, you can fine-tune the perfstat data collection on an ONTAP cluster. If the cluster has a large number of nodes, you may find it useful to reduce the amount of data being collected.