Hi Graemeogden.
thanks for posting this question.
>I receive a "Cluster Lacks Spare Disks" warning even though the cluster has at least 2 spare disks of every disk type available.
Certainly ontap cluster is running out of spare disk.Hence ocum is showing this event.
can you paste outputs of the below commands for us to help you better.
a) disk show -spare
b) node run -node <nodename> sysconfig -r <--- Event details would show which node is having low spare.Run this command against that node.
for the second part of the question
> What is the threshold for this alert and how can I amend it?
Just curious to know why would to like to change the default behavior . Are you being spammed for alert emails?
IMO if you are getting "Cluster Lacks Spare Disks" event on any of your clusters , you are certainly running out of spares on nodes and it should be corrected.(its certainly not false alarm)
Though disk show -spares show enough spare disks , as pradeep mentioned above its possible that the 2 spares left are of diff RPM
output of above command would help in telling you why "Cluster lacks spare disks" is seen.
hope this helps,
-Srinivas