Another approach is to load balance with DNS. You setup a domain that resolves to the set of IP addresses of your mail servers. You might even imploy priority in the DNS records for weighted load sharing. You have the persistence of the session as a bonus. Not so efficient always but way more simple.
Alex On February 10, 2017 1:07:45 AM GMT+02:00, Alex <rightkickt...@gmail.com> wrote: >One approach could be to setup a load balancer (lvs, haproxy) in front >of the servers to share the IMAP load. Make also the sessions >persistent to avoid issues with authentication. > >Alex > >On February 9, 2017 11:57:09 AM GMT+02:00, Patrick Chemla ><patrick.che...@perfaction.net> wrote: >>Thanks all for your answers. >> >>I have at last setup the NAS, and mails are received there. >> >>So I will set the second server and second MTA, and both will receive >>emails. >> >>Next step is to give users access to both servers to retreive emails. >> >>As a load-balancer could help easily for http/https access, how to >deal >> >>with IMAP ports? How to load-balance IMAP ports? >> >>Thanks >>Patrick >> >>Le 29/01/2017 à 14:29, rightkicktech.gmail.com a écrit : >>> A shared storage with glusterfs seems a nice approach. >>> In this way, it doesn't matter which server receives the mail, as >>long >>> as the MDAs of each server write on the shared storage. >>> >>> Alex >>> >>> On January 25, 2017 6:08:59 PM EET, Patrick Domack >>> <patric...@patrickdk.com> wrote: >>> >>> All options, assuming your imap/pop/lmtp are compatable and >>friendly using it. >>> >>> I know dovecot you should only access a mailstore from one host >>at a >>> time, don't just randomly balance things, or it can corrupt the >>index >>> files. >>> >>> Quoting Eero Volotinen <eero.voloti...@iki.fi>: >>> >>> how about mounting ceph or glusterfs disk to message store? >>> eero 25.1.2017 5.18 ap. "Patrick Domack" >>> <patric...@patrickdk.com> kirjoitti: >>> >>> This would not be a good thing to do, as deleted email >>> will magically reappear. Using unison to sync it worked >>> for me, over 10years ago. But these days, just use dsync >>> part of dovecot, and your life will be happy. Quoting >>> Patrick Chemla <patrick.che...@perfaction.net>: Hi >>Wietse, >>> >>> Of course I thought about such NAS solution, but I >>> wanted to check if there is a way with 2 separate >>> disks, with a kind of that could be aware of emails >>> files changes. Actually, the mail server run onto a >>> VM, on a big server. I have another big server with >>> same emails VM, and I just rsync --delete --update >>> from the first one to the second. So I have a full >>> image copy every 5 minutes, but only one real MTA. I >>> will check the NAS option, if there is no other way. >>> Thanks Patrick Le 24/01/2017 à 13:45, Wietse Venema >a >>> écrit : >>> >>> Patrick Chemla: >>> >>> Hi, I have a running Fedora 24 emails server >>> using postfix 3.1.3, with courier. I wonder >>> how to build a pair of MTAs to secure emails >>> at all time, having 2 servers receiving the >>> emails, and users could connect to either >>> server to get emails, maybe on a load >>balanced >>> way. Problems are with synchronization when >>> receiving emails from outside, or emails >>read, >>> emails moved,.... >>> >>> You need a redundant message store. In pre-cloud >>> times, people would use a NAS filer with >>redundant >>> disks, store email as maildir files (one per >>> message) and MDAs would mount that store via >NFS. >>> Perhaps that model still works for you. Does >>> someone have a good guide, howto, doc to achieve >>> this? >>> >>> Thanks for help. Patrick >>> >>> >>> >>> >>> >>> -- >>> Sent from my Android device with K-9 Mail. Please excuse my brevity. > > >-- >Sent from my Android device with K-9 Mail. Please excuse my brevity. -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
