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Hi,
we have two companies with independend IT but sharing the maildomain.
company1 = only sends dkim signed mails for domain.de (no ESA)
company 2 = sends (dkim signed) mails and receives mails for domain.de (ESA C170 cluster)
All incoming and ...
We have outgoing traffic coming from both locations (one with ESA one with regular postfix / linux mailserver).
Both outgoing mailflows are fine and verified successfully for SPF/DKIM/DMARC by random receivers.
The MX-records for our domain point...
ESA (network-> DNS) points to internal DNS-Resolver that is having apropriate TXT records for domain:
me@localhost:~$ dig +short @dns-server-set-up-in-ESAs 18022801._domainkey.domain.de TXT
"v=DKIM1; k=rsa; t=y; " "p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8...
DKIM verify is on. DMARC reports show, that there are issues for mails coming from our other company - but it's not showing it in the header:
<row>
<source_ip>our-public-ip-company1</source_ip>
<count>63</count>
<policy_eval...
dmarc and dkim checking is checked/activated for the matching policy ACCEPTED. As this system provides mail like any other sender (from outside) no specific policy is in place. I supsect that this is by design because it's the same domain name.
