Wikimedia DC's server regularly gets this error message:
error: mediawiki-debug:5 compression program bzip2 is not an executable file
error: found error in /var/www/wikimediadc/public_html/w/debug.log , skipping
Cron sends out an email when this happens; the email always gets stuck in a spam filter and this has been the case for at least a year. It may be prudent to do something about this now that we have sysadmins.