Problems with load balancing cluster on GFS

[John Madden]

> >  Current size of my Imap Server is 2500 users and currently 250 GByte of
> > Mailboxes used (growing and growing).
> Well, we will be talking about something in the range of above 50k
> mailboxes, so a single machine is just out of question. And some sort
> of standby will be needed. I didn't do the concept for this system,
> though, I'm just the one who has to implement it ;)

A single machine is not out of the question for that number of
mailboxes, but is perhaps for the amount of traffic driven by your user
behavior -- that's what you need to determine.  We happily run 350k
mailboxes on a single system with the determining factor being I/O
contention during mail delivery.  Depending on your storage, you won't
necessarily be able to fix that contention by running multiple machines.
I wouldn't count out a single machine with lots of (relatively small)
storage pools to build performance.  

John




-- 
John Madden
Sr. UNIX Systems Engineer
Ivy Tech Community College of Indiana
jmadden at ivytech.edu