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i have multiple ip addresses and domains and configured postfix to use the correct ip address according to the sender-address using a map

now there are still servers answering with a forged 550 but i can't determine why? from what i can see from the logs and email headers the correct ip and domain are being used.

excerpt from

example-sender-org unix - - - - - smtp -v
        -o smtp_bind_address=11.x.x.x
        -o syslog_name=postfix-example-sender-org

Example E-Mail Header:

Received: from ( [11.x.x.x])

Example postfix debug log (smtp -v):

deliver_message: from
smtp_parse_destination: smtp
connecting to port 25
dns_query: (MX): OK
dns_get_answer: type MX for
smtp_addr_one: host
lookup type A flags 128
dns_query: (A): OK
dns_get_answer: type A for
begin address list
pref   50 host
end address list
smtp_find_self: not found
smtp_connect_addr: bind 11.x.x.x
smtp_connect_addr: trying:[10.x.x.x] port 25...
vstream_tweak_tcp: TCP_MAXSEG 1448
global TLS level: none
<[11.x.x.x]:25: 220 ESMTP ( (even more power) Tue, 15 Oct 2013 12:
>[11.x.x.x]:25: EHLO
<[11.x.x.x]:25: 550-Forged HELO: You are not, please use sender
<[11.x.x.x]:25: 550 domain as HELO/EHLO not recipient domain.
>[11.x.x.x]:25: HELO
<[11.x.x.x]:25: 550-Forged HELO: You are not, please use sender
<[11.x.x.x]:25: 550 domain as HELO/EHLO not recipient domain.

side note: my mx0 for the sender domain does not point to the same ip address... is it possible that thats the problem? i assumed the a-record was required...

i found this (third answer):

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just a note: i did this test and the helo/ehlo section was ok – greenone83 Oct 15 '13 at 11:48
another note: having multiple domains but less ip addresses, if i want to send emails via all domains, then the helo/ehlo check effectively forces me to have a ip address per domain, because otherwise i can never make sure that mx0, sender-domain and reverse dns are matching. – greenone83 Oct 15 '13 at 12:06

turns out the hoster requires you to use your mx0 as heloname, all other are discarded...

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