noun
corrective maintenance
Computing term for maintenance performed after a failure or problem has occurred, as opposed to preventive maintenance.
システム障害が発生したため、事後保守を実施した。
Because a system failure occurred, corrective maintenance was carried out.
予防保守 is preventive maintenance, performed regularly to avoid failures, while 事後保守 is corrective maintenance done after a problem arises.
Compound of 事後 (after the fact) and 保守 (maintenance).