On Mon, Nov 8, 2010 at 4:51 PM, Stan Hoeppner <s...@hardwarefreak.com> wrote: > ahmad riza h nst put forth on 11/8/2010 3:05 AM: > >> yes i read the manual before, it's said "Virtual aliasing solves one >> problem: it allows each domain to have its own info mail address. But >> there still is one drawback: each virtual address is aliased to a UNIX >> system account. As you add more virtual addresses you also add more >> UNIX system accounts. The next section eliminates this problem. " >> this what i want to understand about. how bad the system or the >> postfix it self if we use thousands of unix system account to host >> virtual users, or it just ok with it ? > > 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. > 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. 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. > Both of these things are relatively inexpensive, and it's better to > install them before the machine goes into production, so won't have > downtime when you find you need to install them later. > > RAID1 implies only two disks with a single spindle of throughput. One > spindle won't be nearly enough throughput for "thousands" of users. At > minimum you should have an 8 disk hardware RAID5 array in your dl180 g6 > for storing: > > 1. System log files > 2. Postfix spool directoty > 3. Dovecot IMAP/POP mail store directories > 4. Mysql database if you choose to move it to this box > 5. Any other files with very high read or write access frequency > > 15k SAS drives would yield the best performance, but 7k SATA drives will > be considerably less expensive and offer greater capacity. Regardless > of which you choose, you need vastly more than 1 spindle of throughput > for over 1000 users. Given the relatively low cost of SATA drives, I'd > say you should install as many as will fit in the box, and configure > them as one RAID5 or 6 array, with one standby spare. > > I highly recommend you use Dovecot LDA for mailbox delivery if offerig > IMAP, especially if you intend to configure ManageSieve. Using LDA > updates the Dovecot indexes during delivery, decreasing MUA response > times, as the emails are already indexed when the user accesses an > email, instead of during the process of accessing the new email. The > latter is the default indexing mechanism. > 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 > > -- > Stan > -- http://blog.rizahnst.org
