I have servers which are still running well but are over 5 years old. They are still doing the job perfectly and there will be no advantage to upgrade the servers, should I just let them run forever or should I schedule maintenance to replace the servers, or parts thereof, with new hardware? I fear that a server failure might cost data loss and more down time than scheduled maintenance. These servers are used for on-line point-of-sale, accounting, CRM and management information.
Preventive maintenance, such as replacing fans and vacuuming out dust, is not possible due to the remote location of the servers.
Also keep in mind the "bathtub curve" of failure rate with time. New hardware is more likely to fail than hardware that has been burned in for a while.
How do you tell a client who is very happy with a long-time trouble-free server that he now has to spend money to replace it because it is too old?
Finally, are there any monitoring tools for hardware problems such as voltage, temperature and fan speed that can be run remotely?