I had upgraded several of my websites to IPv6 (it was not worth it, the
only traffic is from Google's IPv6 search bot).
I recently migrated all my websites to a new host, and upgraded my
squirrelmail webserver to IPv6 as well.
I use qmail as a local mail agent.
Seemed to work fine, until I tried to send mail to a non local address.
Then I get the 503 "not in my rcpthosts" error.
And here's my tcp.smtp file:
It should be fine, right? Here's the log from a failed send:
@4000000053433835313d201c tcpserver: status: 1/20
@40000000534338353142215c tcpserver: pid 29599 from ::1
@4000000053433835314b54d4 tcpserver: ok 29599 xxxxxxxxx.org:::1:25 localhost:::1::53170
@40000000534338353b43610c tcpserver: end 29599 status 256
@40000000534338353b436cc4 tcpserver: status: 0/20
The second line shows "from ::1". This is the ipv6 way of representing localhost!
My qmail and assorted tools do not support ipv6 (I'm not sure if any of DJB's tools do, yet).
So the RELAYCLIENT wasn't getting set.
The fix is to replace the localhost (in the squirrelmail config) with 127.0.0.1, forcing IPv4.