No mechanical device with moving parts lasts forever, and computer servers are no exception. We prefer to plan in advance for this and swap out hardware that's starting to show it's age long before any failure. This way the migration can be scheduled to be done at a time when traffic is typically at it's lowest.
That's us...keeping it fresh!
On Saturday, May 7, 2011 at 10pm EDT (GMT -4), we will begin migrations to a newly provisioned server. There will be some downtime while the accounts are migrated. We generally do not expect the downtime to exceed 15 minutes, but it is based on many variables and may (rarely) exceed 30-45 minutes. The data center will be actively monitoring all accounts for the duration of the migration.