Beginning at 11:59pm on July 18, 2004, Planet engineering will begin upgrading the IOS code on all of our Cisco 3750 Layer-3 switches. You are receiving this email because you either have a server that will be affected by this work, or are listed as a contact for a server that will be affected by this work. These upgrades are necessary to correct a critical flaw in the existing code that they are running. Engineers will upgrade one switch at a time, making sure that the current one returns to normal service before moving on to the next one. The total time for each switch to be upgraded and reloaded will be about 10 minutes (barring any unforeseen issues). During the reload, your server will be unavailable. The new code has been running on production switches for several weeks without issue, so we don't anticipate any problems with the upgrade.
We want to stress that while the maintenance window is 3 hours total, the anticipated downtime for any single server is only about 10 minutes. Because we are staggering the reloads, it will take a couple of hours to complete all of the switches.
Just a lil FYI