Desired characteristics of a server

I've been working on a body of characteristics that a server should ideally have. So far, I have:

Documented

A server should be documented. The documentation should provide enough information to anyone who has to service the server, including allowing them to rebuild the server if necessary. The documentation should also satisfy any auditing requirements of the organization.

Verifiable

A server should have a given known state, described in the documentation, and it should be possible to programmatically determine whether or not the system is in that state.

Secure

A server should be protected against any attacks made by unauthorized entities that would disrupt the server or provide the attacker with information they are not authorized to have.

Monitored

A server should be monitored to ensure that it is in its documented state. Any deviation from that state, either through an uncoordinated change made by operations or through actions of an unauthorized party, should be detected automatically and the operations staff should be notified accordingly.

Backed up

A server should be backed up. Data that may have been lost due to error or tampering should be recoverable within the documented parameters.

Replaceable

A server should be replaceable. If the server fails or significantly goes out of its documented state, any technician should be able to provision and install a replacement while the faulty system can be diagnosed, inspected, and, if possible, corrected outside of the production environment.

Manageable

A server should be manageable and serviceable by any technician authorized to work on it.

Measured

A server should have its statistics measured and recorded on a regular basis. This data should be usable for planning activities and to monitor trends on the server.

Functional

A server should fulfill its documented role.

Some of these are admittedly characteristics of the server's environment and its technicians rather than of the server itself.

If you think I've overlooked anything, please let me know.

Edit: I added the last two originally as comments. I've added them to the actual post to make it easier for anyone who visits in the future.