[horde] server capacity ?

[Niels Dettenbach]

Hi,


this hardware setup should be more then enough - at least if you run a optimal software configuration (suitable kernel and binaries). In the past i tried to avoid CentOS where possible (because of the inflexibility and the "horrible" yum package management) - so i can't say anything more about it.

We have implementations with 1GB RAM for (around) 30 active office users. U320 SCSI should be nice (assume you run RAID 0,1 or 10 something like that). 

I would recommend cyrus too (with squatter and idled activated) as your POP / IMAP if you want to run it as a comfortable IMAP server. It brings a fast fulltext indexing engine and allows performance optimization in different ways (i.e. partitioning). Not at least it offers SIEVE filters and the afaik most complete IMAP proto implementation. With idled your clients did not have to poll every minute to get their mail fast signaled / received (as soon as the clients are able to do imap idle )...

If you have more then 1 logic disk it may make sense to work with cyrus partitions to divide the loads onto different disks. Bringing /var on own disks could improve i/o performance - but this is not a requirement.

I did not know xmail, but i can recommend the well known and hardly proven EXIM (ideally build from source as "usual" for professional EXIM usage) - this is not really difficult (just follow exims INSTALL doc) but allows to build a very small and efficient MTA/MDA binary which works very efficient in RAM, on CPU and i/o subsystems - and combines smart with Cyrus / SIEVE. Integration of MySQL and/or SASL is relatively easy and very flexible.

Usually Horde / MySQL is consuming most ressources (RAM / CPU) if your machine act's just as an satellite host (not directly as MX on the public net). Try to use caching in horde and - if the defaults not fit your needs - play with the MySQL config.

hth
Cheers,

Niels.