recommendations for large mail system
I'm involved in project to implement email system for 50k current account,
and option to expand system in 50k blocks. Quota 500MB and availability 99.99.
Prototype is server-pair in ha setup (hearbeat, mon etc), tested with
schema, cyrus app.level replication and drbd. Filesystem is lvm+ext3.
Machiens are 3Ghz dualcore xeons with 6G of ram.
We plan to put 50k accounts per server(pair), based on assumption
that 5% of them are on-line at maximum. 90% of users are web-client,
rest are native imap clients. Prototype seems to be able to handle 2.5k
simultaneous, almost idle imap sessions without problem.
Problem is that we have no idea of real IMAP-usage patterns. Using
home-made test-programs is probably misleading.
I appreciate if you would like to share your experience to build
large email system, especially comments on accounts-per-server,
filesystem and test-methods are welcome!