Followup and status
Old iris has been rebuilt as a VM host and re-installed at Stephouse.
Yesterday evening, knod and iris were moved to the new VM host. Old
knod is still running at Canvas Host, but DNS no longer points at it,
and it will be shut down shortly. The other remaining VM running at
Canvas Host is drei. This serves our irc server and cwnmyr and maybe
some other things. It has been taking about 6 hours to move each VM,
considering the various steps involved, moving a 200GB logical volume,
so some downtime is to be expected. Of course, while tapping my toe,
waiting for the transfers to complete, various efficiencies have
occurred to me, for example downtime could be minimized by using LVM
snapshots, but I've decided I would rather have everything happen
cleanly than minimize downtime, and 6 hours for a one-shot thing (per
VM) is tolerable. I may do drei this afternoon or evening. I'll be
calling Canvas Host to remove our box there on Monday, ahead of the
deadline.