Perhaps so, but this is now what's happening out in the real world. We also see the same behaviour from Yahoo (who started this before the others a couple of years ago) and from Gmail, and as I said before, our main client thought it was a good idea and did the same in their SMTP-server. I think it would be a good idea to have Exim play nice with these rules.
A correct implementation would be to say something with a message at the FIRST email you decide to block, and then block the IP-address after that. That way our SMTP-server would send as much as it could, and then get blocked for a while - which would indicate to Exim that the host is down (=retry rules in effect), but I understand why they've done it like this - since they probably have some special rules that would let a unique message slip by anyway, not to mention the problem they might have to block an IP-address since they probably have quite a large load-balancing setup with many entrypoints. I can not change the way Microsoft, Yahoo, Gmail och others do business - but I might tweak Exim to play better with their - somewhat bad - rules. Cheers! /Charlie 2017-10-19 13:13 GMT+02:00 Evgeniy Berdnikov <[email protected]>: > On Thu, Oct 19, 2017 at 11:19:53AM +0200, Charlie Elgholm wrote: >> * 2017-10-18 11:42:23 1e4kjd-0006nY-4L SMTP error from remote mail >> server after pipelined sending data block: 421 RP-001 (COL004-MC3F9) >> Unfortunately, some messages from <ip> weren't sent. Please try again. >> We have limits for how many messages can be sent per hour and per day. >> You can also refer to >> http://mail.live.com/mail/troubleshooting.aspx#errors. > > Microsoft guys are doing wrong thing. They should reject connections > for specific ip-address, or return 4xx in place of greeting message > and on MAIL, shuch errors could be treated as host-specific rejections. > If status-codes 4xx are emitted on RCPT stage, such rejections are > recipient-specific, so Exim could try other mails for the same MX. > > This log fragment looks like response to DATA, with pipelining on. > It's a bad idea to put the ip-address rejection here. > Legal 4xx response to DATA may be caused by problems with disk space, > memory, system-wide filter (antivirus, ex) hangup on the receiver host. > All these conditions are not related to specific recipient. > So I think Exim havŠµ better to treat 4xx on DATA as host-specific. > -- > Eugene Berdnikov -- Regards Charlie Elgholm Brightly AB -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
