[Splitting this off from bug 69096]
Logging out of http://commons.wikimedia.beta.wmflabs.org/ I get with Firefox 31:
Sorry! This site is experiencing technical difficulties.
Try waiting a few minutes and reloading.
(Cannot contact the database server: Unknown database 'incubatorwiki' (10.68.17.94))
Version: unspecified
Severity: normal
We deleted a bunch of wiki projects / databases on the beta cluster (T48104: reduce the number of wiki on beta). They are still referenced in CentralAuth global usernames though.
There are no more any occurrences of incubatorwiki in the CentralAuth database:
mysql> select * from localuser where lu_wiki='incubatorwiki'; Empty set (0.00 sec) mysql> select * from localnames where ln_wiki='incubatorwiki'; Empty set (0.00 sec) mysql> select * from globaluser where gu_home_db='incubatorwiki'; Empty set (0.02 sec) mysql>