Interesting gotcha with datastore heartbeating in vsphere HA

[danswartz]

So I deployed a new NAS which had been serving up a datastore to vsphere. One of the functions was a repo of ISO files. Another was acting as the 2nd heartbeat for HA. Unnoticed by me, the permissions on the NFS share's root were wrong, and vsphere hosts were unable to write heartbeat files. But... this was not indicated anywhere in the vcenter GUI (as opposed to the warning you get if you have < 2 heartbeat datastores.) Kinda weird omission, if you ask me... I only noticed this because I had 'zpool iostat 10' running on the NAS and was surprised to see no writes to the NFS share.