The secondary MX machine is now fully deployed and in use by over half our users; no last minute panic at all when the switchover was made, so I'm feeling pretty good about things right now!

The initial deployment of this additional machine was much slower than expected, because I needed to make significant changes to the way our service worked - It is pretty easy to setup a cluster these days, even a dynamic one using a shared/replicated database.

But the code that we run is a lot more involved than that. The ultimate goal of the secondary MX was to configure a box that would be able to handle mail processing in the event of the complete failure of the primary machine.

With that idea in place it became an interesting project to complete in its own right, and thanks to some brief moments of downtime I even demonstrated that this was possible.

Thankfully now that the second machine is in place adding a third, fourth, or even fifth machine will be trivial. Although I might have to come up with a naming policy for the new machines!

To celebrate the arrival of the secondary machine I've created a status page which will show the state of both boxes:

• http://status.mail-scanning.com/

(As with this blog, and our support system, this status check is hosted on a completely independant third machine :)