[Mailman-Users] Setting up a failover system for Mailman

[The List Server Administrator at UNH]

Folks,

     We maintain a failover system for our primary web server system.
     Using "rdist" we copy over the server's data tree every hour to
     the failover system.  Should the primary system fail, we can put
     the failover system on-line and have it answer to that address.
     The idea is that (we hope) at most only an hour's worth of
     updates made by our content providers (faculty, staff, and
     students) would be lost.

     We'd like to setup something similar for our mailing list
     services.  I was wondering if anyone else has already gone down
     this road and would appreciate any advice.  One of the things I'm
     concerned about is that a list server (unlike a web server?) is
     very 'stateful'.  That is, lists go through states of waiting to
     have a message to be distributed, in process of having the
     message delivered, and then filing away the message that was
     delivered, archiving copies, etc.  For example, I would expect
     that Mailman, on start-up, is designed to detect if it was
     interrupted, say by a system crash, in the delivery of a posting,
     and would queue that posting for retry.

     So my question is, would it be strictly necessary to stop the
     server each time before capturing the data tree in order to be
     sure the server's files would be in a stable enough state?

     To look at it another way, this is really just a backup
     procedure (although one that is potentially done much more
     frequently then the usually nightly backups).  So does your site
     bother to shutdown Mailman before doing your nightly backups?
     Is there the danger of having a restored server data tree that will
     not run if this is not done?

     TIA for any insights or ideas.


                                           Cordially,
                                           The List Server Admin
                                           list.admin at unh.edu
                                           (currently Bill Costa)