[Mailman-Users] Server Migration Issue -- Only Some Members Receive Email?

[Greg Sims]

I recently migrated from RHEL 6 to CentOS 7.  The migration seemed to be
straight-forward by:

   - creating three mailman lists
   - for each of the list directories
      - copy files from the old to new server
      - list options and membership seems good

I have an issue and have run out of ideas.

[root at ray06 log]# cat /var/log/maillog.processed /var/log/maillog | grep
'Mar  9' | grep status=sent | wc
   6176  109377 1554218

The above looks at our maillogs for email that was sent on Mar 9.  The
answer is 6,176 emails sent.  We have over 20,000 subscribers total on our
three mailman lists.  It appears that only some of the subscribers are
receiving email.

I also looked at this from the perspective of one ISP -- gmail.com.

[root at ray06 email]# cat /var/log/maillog.processed /var/log/maillog | grep
'Mar  9' | grep status=sent | grep gmail.com | wc
    976   18544  254501
[root at ray06 email]# sudo /usr/lib/mailman/bin/list_members english-devotion
| grep gmail.com | wc
   4945    4945  110190

The maillogs show 976 gmail.com emails sent while one of our lists has
4,945 gmail.com members.  Again it appears that only some members are
receiving email.

I looked at /var/log/mailman/* and things seem normal.  I'm not sure how to
proceed from here.