Dear all,
I’m using spamcop.net to submit spam reports on a regular basis.
Unfortunately spamcop anaylzes the email headers and stops if an internal network is being detected.
This happens sometimes, and I don’t know the exact cause yet, but I can say thet rspamd did not rewrite the header of the spamemail, instead it seaid no-action.
Why does the header show the internal IP fd4d:6169:6c63:6f77::c for my mailserver instead of the external one?
My docker containers “mailcowdockerized-postfix-mailcow-1” uses the ipv6 addres fd4d:6169:6c63:6f77::c.
A received-header begins like this:
Received: from mail.meinedomain.de ([fd4d:6169:6c63:6f77::c])
by 6b8c305be537 with LMTP
id WFhiKY85UWijixoAhYVPlA
(envelope-from <x>)
for <x>; Tue, 17 Jun 2025 11:46:55 +0200
My br-mailcow uses internal ips (ipv4 and ipv6) only:
ip addr show br-mailcow
395: br-mailcow: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether be:03:4e:xx:xx:xx brd ff:ff:ff:ff:ff:ff
inet 172.22.1.1/24 brd 172.22.1.255 scope global br-mailcow
valid_lft forever preferred_lft forever
inet6 fd4d:6169:6c63:6f77::1/64 scope global nodad
valid_lft forever preferred_lft forever
inet6 fe80::bc03:4eff:feb0:c473/64 scope link
valid_lft forever preferred_lft forever
This corresponds to the settings in docker-compose.yml:
networks:
mailcow-network:
driver: bridge
driver_opts:
com.docker.network.bridge.name: br-mailcow
enable_ipv6: true
ipam:
driver: default
config:
- subnet: ${IPV4_NETWORK:-172.22.1}.0/24
- subnet: ${IPV6_NETWORK:-fd4d:6169:6c63:6f77::/64}
Why isn’t a public routed ipv6-network being used?
Is there a chance to rewrite headers automatically to show external IPv6-IPs only?
how do you do spamcop.net submissions with mailcow?
