Re: What exactly is hostid used for?

> But frankly, why would you ever bother with disabling it?

Because "apps (often aka anti-privacy tools)" and nic's and attacks
can read your unique and paste it into the internet, and do whatever
else with it. Would not be surprising if javascript browsers are reading
such things. Nor would some environments want it embedded in say
offsite backups of zpools, etc.

If NFS ZFS HAST and other apps can't take a manually supplied app-specific
string to use instead of reading whatever happens (or not) to be in hostid, or
even continuing to work with just null, then that represents bugs in privacy,
validation testing, and debugging capability that need be fixed.