[horde] Issue with Horde wiki

[Mike]

Hopefully I'm not repeating a known issue but when I go to  
wiki.horde.org, I get:

A fatal error has occurred
MISCONF Redis is configured to save RDB snapshots, but it's currently  
unable to persist to disk. Commands that may modify the data set are  
disabled, because this instance is configured to report errors during  
writes if RDB snapshotting fails (stop-writes-on-bgsave-error option).  
Please check the Redis logs for details about the RDB error.

Mike