Word of the day...

zombie server (comatose server)

A zombie server is a physical server that is running but has no external communications or visibility and contributes no compute resources; essentially, it consumes electricity but serves no useful purpose. Zombie servers are also referred to as comatose servers.

Zombie servers are often created because user-requested applications end up getting no use or almost no use (typically defined as under six percent). Other causes include redundant or legacy applications and services that have been replaced. An estimated one in three servers in North America falls into the "undead" category.