The only difference I would have on this server is I would make it a 10 raid and not raid5. This is a much more higher performing with all the writes to maildir. Its also better fault tolerance.
On Mon, Nov 8, 2010 at 7:25 AM, Stan Hoeppner <s...@hardwarefreak.com>wrote: > ahmad riza h nst put forth on 11/8/2010 4:08 AM: > > >> You won't have local system accounts. Just setup Postfix and Dovecot to > >> query your current mysql domain and user database. It may take some > >> tweaking, but what doesn't? ;) > >> > > > > thanks for your reply stan, > > > > the problem is we have to use webmin + virtualmin for user interface > > (control panel), and it seems virtualmin doesn't support postfix > > virtual user via mysql db, indeed they do it alias with unix system > > users. > > "Have to"? There are alternatives, such as > http://www.ispconfig.org/ispconfig-3/ > > In the absence of Virtualmin support for your mysql user db, how are you > going to populate the local UNIX user account database on the new > system? Does a tool already exist allowing you to do so? If not, and > you will have to write such a tool, I suggest you focus your efforts on > writing a tool/plugin to allow Virtualmin to directly read/write your > mysql user db. > > >> Are you using Dovecot for IMAP and POP or just POP? > > > > IMAP and POP. > > > >> > >>> our hardware is hp dl180 g6 (a xeon quad core + raid 1 + 4G ram) > >> > >> Ok, that answers one of my previous questions. This system isn't nearly > >> strong enough for thousands of users. You should: > >> > >> 1. Bump the RAM up to at least 8GB > >> 2. Install the second matching quad core processor > >> > > > > i understand, but we only use this server for mailboxes only, so there > > will be no spamassassin or clamav etc on the server, we have separate > > mail filtering (mx) on another servers. > > As you should. So, can you disable those buttons so your users can't > access them? Or will you allow them to press the buttons, but they > won't really do anything? The SA config in Virtualmin is per user is it > not? > > > currently we have another mailbox server (it hp dl 180 g6 too) with > > qmail and vpopmail, there are about 11 thousands virtual user on the > > server and it still running well at this time, thats why we think > > postfix and dovecot can do it with same hardware. > > Ahh, then you're ignorant of IMAP processing and communications > patterns. The load generated by IMAP clients versus POP clients cat be > well over 100 fold, especially if the clients are not syncing messages > locally. Each click on a mail folder or email generates a packet to the > IMAP server and a response packet back to the client. Multiply that by > 1000 concurrent clients. The communication pattern is more akin to > telnet or SSH. POP is more similar to FTP. One is constantly > interactive. The other creates a burst as is then done. IMAP generates > an order of magnitude more load on a server than POP does. You've > apparently not heard of body searches on IMAP mailboxes. Once client > can tie up an entire server CPU core for 10-20 seconds at a time > searching an IMAP folder containing 5,000-10,000 messages in it. This > is probably the heaviest hitting IMAP feature your users could take > advantage, although there are others that will suck up server resources. > POP has none of these features, so load is directly correlated to the > number of concurrent logins and new messages in the queue. There are > many more performance variables WRT IMAP servers. > > > i will read this, thanks. > > > >> http://wiki2.dovecot.org/LDA > >> http://wiki2.dovecot.org/LDA/Postfix > >> http://wiki2.dovecot.org/Pigeonhole/Sieve > >> http://wiki2.dovecot.org/Pigeonhole/ManageSieve > > Join the Dovecot mailing list. Post what you're requirements are, how > many users you have, what you plan to do, and what hardware you plan to > use. Ask for advice on the mysql userdb issue WRT Virtualmin. Ask for > opinions on what hardware you need to host 11,000 IMAP users. > > http://www.dovecot.org/mailinglists.html > > -- > Stan >
