We will have a scheduled maintenance window tomorrow from 6:00am to
8:00am PST. The following changes will take place:
* 6:00am PST (1400 UTC) stage.mozilla.org – core operating system will be upgraded from RHEL4 to RHEL5.  Expected downtime 60 minutes, things may not behave quite right for an hour or two after the upgrade as the loose [...]

We will have a scheduled maintenance window tomorrow from 6:00pm to  7:30pm PST. The following changes will take place:
* 6:00pm PST (0200 UTC) bugzilla.mozilla.org update.  We’ll be
upgrading Bugzilla from version 3.2.4 to 3.4.3 (bug 503055).  Duration 90 minutes.
Feel free to comment directly if you see issues past the planned  downtime.

We will have a scheduled maintenance window tonight from 5:00pm to  8:00pm PDT. The following changes will take place:
* 5:00pm PDT (0000 UTC) addons.mozilla.org database hardware upgrade. We’ll be adding additional RAM to the master database server for addons.mozilla.org. (bug 522112). Duration 30 minutes (although the site may stay down pending completion of the file [...]

Due to a disk drive running out of space, the slave server for our C01 database has gotten corrupted, and needs to be resynchronized with the master database.  This will necessitate taking the master database offline for the duration of the re-sync, which should take approximately 25 minutes.
This will begin at 11am PDT (about 10 [...]

We will have a scheduled maintenance window Thursday night from 7:00pm – 11:00pm PST (0300 – 0700 UTC). The following changes will take place:

7:00pm – We will be replacing a faulty midplane on a blade chassis containing 14 servers which support the following services:  addons.mozilla.org, download.mozilla.org, crash-stats.mozilla.com.  With the exception of crash-stats, the affected servers [...]