Hi everyone, I'm planning to deploy a SMTP(Sendmail) and IMAP(Cyrus) server on a mid-sized organization(~300 remote users, dunno about messages/day), and since is my first IMAP server (until now we do only POP), I have some questions about sizing.
First, about hardware requirements. I had tought to use a Dell 1850, 2GB RAM with two controllers: a PERC4e/Si for system + sendmail queue, and a PERC 4e/DC connected to a PV220s, with 7x300GB (half of backplane) for imap data (4 or 6 discs in RAID-10 + 1 hot spare) . I think it should be enough, but it's really? (the hardware it's already bought, so I really hope so). Any recommendations about stripe size or raid configuration?, which ami version to use? -stable one? How ami's performance compares with FreeBSD's amr? I understand that is advisable to run softupdates on the imap and /var/spool partitions, and to disable fsck on boot, but what about increasing buffer cache size? 5% of physical memory seems a bit low for an I/O intensive app as Cyrus is. About resource limits of _cyrus user and sysctl values, are there well known values? Should I increase kern.maxfiles for example? I wouldn't like to learn it at production time. Well, this are my questions. May be the hardware is overkill for our load, but sizing hardware without prior experience it's always a difficult task, so if anybody wants to share their experience... Thanks in advance, Samuel
