Am 21.04.2014 22:26, schrieb Wietse Venema: > Wietse Venema: >> A possible solution for load balancing is to introduce a new map >> type that makes random selection. >> >> randmap:/file/name >> >> The file contains a list of reponses, one response per line, >> ignoring leading whistespace, trailing whitespace, and empty >> lines. Each map query returns a randomly-selected response. >> >> randmap:!one!two!three >> >> Split the text after ":" on the first character, producing a >> list of responses (one, two, three). Each map query returns a >> randomly-selected response. >> >> That should be enough to load-balance deliveries over mail delivery >> transports. >> >> The following example will deliver local mail locally and load-balance >> non-local mail over smtp0: and smtp1:. >> >> /etc/postfix/main.cf: >> transport_maps = hash:/etc/postfix/transport, randmap:!smtp0:!smtp1: > > Here are some more simple building blocks to encourage clean > solutions. > > - Using similar syntax as the randmap feature, a roundmap feature > that implements round-robin selection instead of random selection. > > - An smtp_bind_addres_maps feature that searches a map by destination > IP address. This could be combined with randmap or roundmap selection. > > - A randmap(8) or roundmap(8) pseudo-delivery agent that selects a > real delivery agent (or transport[:nexthop]?) from a list, with a > user interface similar to randmap/roundmap lookup tables. This > can, for example, load-balance over arbitrary SMTP client settings. > > - An option to disable or limit the use of the one-element cache > in the Postfix address resolver client. > > I'm getting tired of questions about relayhost load balancing or > source IP address diffusion. > > Wietse >
Perhaps include some simple "weight" mech too, if possible Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein
