[Mailman-Users] replicating lists

[Brad Knowles]

At 3:37 AM +0530 2004-07-09, Yogesh Subhash Talekar wrote:

>  I have configured Mailman on two servers. Should one fail I will route my
>  traffic towards the secondary server. But my problem is how do I keep the
>  lists on both the servers in synchronisation?

	Running two separate mailing list servers for the same mailing 
list is a very difficult task.  To make this work, you'd have to 
share all the critical files, deal with file locking across networks, 
etc....  This is much, much harder to do than it sounds.  I don't 
know of anyone who has done this for a mailing list server.

>  I can use transparent ssh to copy file from one server to other on regular
>  intervals. So can I just copy few files/directories from primary server to
>  the secondary? Will those lists then will work?

	It takes a lot more than just copying files around.  The problem 
is that these files are constantly changing, and they might be 
changing in different ways at the same time on both machines.  How do 
you sync that?


	One thing you could do is to have a warm spare server.  You'd 
have to decide how current the backup files would need to be -- maybe 
an hour old would be okay, in which case you might be able set up a 
cron job to run rsync every hour.

	If the primary server were to go down, you could quickly 
configure the warm spare server to step into the role, but this would 
take quite a bit of work to make everything happen smoothly.

-- 
Brad Knowles, <brad.knowles at skynet.be>

"Those who would give up essential Liberty, to purchase a little
temporary Safety, deserve neither Liberty nor Safety."

     -- Benjamin Franklin (1706-1790), reply of the Pennsylvania
     Assembly to the Governor, November 11, 1755

   SAGE member since 1995.  See <http://www.sage.org/> for more info.