On Tue, 11 Oct 2011, Noel Jones wrote:
This messages was rejected by the reject_unknown_client_hostname restriction.
Noel, That's what I assumed.
That's only half of it. You also need to check: $ host 67-23-35-254.static.slicehost.net. Host 67-23-35-254.static.slicehost.net. not found: 3(NXDOMAIN) *that* is why the host is labeled unknown, and was rejected by your rules.
Yes.
The usual suggestion is to not use reject_unknown_client_hostname; that restriction will reject a lot from legit but misconfigured clients.
Huh! I don't recall reading this before. I'll consider it. However, I cannot recall running into this issue with a legitimate source before. See below.
Worse, the client IP hostname is under the control of the ISP, and few "consumer" ISPs offer customer control of the IP hostname. So the person on the other end may not be able to fix this misconfiguration.
I wrote to technical support at slicehost.net and sent them the appropriate lines from /var/log/maillog. They responded quickly that the owner(s) of the cloud server on that particular slice could fix the reverse lookup address for their IP address. I passed on that information, along with the suggesting that slicehost.net tech support could advise them on just what to do. I see a lot of gmail and yahoo accounts on that mail list (now that I'm receiving messages with the fix in /etc/hosts) so it may well be that I'm the only subscriber using postfix and an MTA and whatever they did to make the address work with gmail broke it for postfix. Pure speculation on my part. Thanks very much, Rich
