Every five minutes or so, I’m getting an error message like this:

Traceback (most recent call last):
 File "/usr/lib/mailman/cron/gate_news", line 284, in ?
   main()
 File "/usr/lib/mailman/cron/gate_news", line 264, in main
   process_lists(lock)
 File "/usr/lib/mailman/cron/gate_news", line 194, in process_lists
   for listname in Utils.list_names():
 File "/usr/lib/mailman/Mailman/Utils.py", line 96, in list_names
   return Site.get_listnames()
 File "/usr/lib/mailman/Mailman/Site.py", line 110, in get_listnames
   for fn in os.listdir(mm_cfg.LIST_DATA_DIR):
OSError: [Errno 2] No such file or directory: '/var/lib/mailman/lists'

In /etc/cron.d/mailman,

# Every 5 mins, try to gate news to mail.  You can comment this one out
# if you don't want to allow gating, or don't have any going on right now,
# or want to exclusively use a callback strategy instead of polling.
#0,5,10,15,20,25,30,35,40,45,50,55 * * * * mailman /usr/lib/mailman/cron/gate_news

I don’t really understand what gating is and I don’t think we’re using it. So I’ve commented it out.