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Sam Grabham wrote: > Sendmail stuff ignored. I use a mail server that doesn't require me to learn M4 just to configure it. > ###################### > > If you have 2 or 3 MX records, will grey listing cause the sending smtp to > try the next server? Yes All the MX servers should use the same greylist database. One might ponder if you really need secondary servers, since by definition if you are using greylisting you are assuming that most of the reasons for secondary MX's are now long gone. Leaving mostly scalability, which can generally be done with one MX, and some sort of load balancing at the server farm if and when needed. > ###################### > > When a ISP has a group of SMTP servers, how do they centralise the mail for > POP3 etc, do they sync the mail to a master server for all clients to > connect to? > > Has any one got a good URL for this solition? > > ####################### I doubt there is a one size fits all solution. One can imagine multiple POP3 servers sharing multiple disk storage back ends, scaling fairly easily. Certainly when I did a design for such it was pretty easy to see how to scale SMTP delivery to multiple servers for each stage of delivery and reading of email. All the is really needed is the mail boxes are split across servers. It is fairly common to say break down directory structure by part of the name. So "/mail/s/i/simon@xxxxxxxxxxx/..maildir.." and "/mail/n/e/neil@xxxxxxxxxxx/..maildir..", but one could use a hash just as easily and it might make for a better division of load. Then as the email system scales just mount different letters from different servers "/mail/s" from server 1 and "/mail/n" from server 2. The above scheme easily scales to many backend mail storage servers, although one would want to think hard about the details before scaling it up. I dare say that there are more sophisticated solutions - but maildir makes it pretty easy since there is no requirement to do locking, so good old fashioned NFS can be put to work in such a design. -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html