Hosts to retire:
* Ops steps
** [x] All system services confirmed offline from production use (MySQL is now stopped)
** [x] Set all icinga checks to maint mode/disabled while reclaim/decommmission takes place.
** [x] Remove system from all lvs/pybal active configuration
** [x] Any service group puppet/hiera/dsh config removed
** [x] Update site.pp with `role::spare::system` https://gerrit.wikimedia.org/r/#/c/405278/2/manifests/site.pp and https://gerrit.wikimedia.org/r/#/c/401708/3/manifests/site.pp
* DC ops
** [x] Disable puppet on host
** [x] Remove all remaining puppet references (include `role::spare:system`)
** [x] Power down host
** [x] Disable switch port
** [x] Switch port assignment noted on this task (for later removal)
** [x] Remove production dns entries
** [x] Puppet node clean, puppet node deactivate
** [x] System disks wiped (by onsite)
**  System unracked and decommissioned (by onsite), update racktables with result
**  Switch port configration removed from switch once system is unracked.
**  Mgmt dns entries removed.