I am getting a lot of spam on my exim4 mailserver, much of which is logged with "no host name found for IP address ..." and "no IP address found for host ...". The acl_check_rcpt acl is mostly set with the debian defaults.
I enabled CHECK_RECPT_VERIFY_SENDER, which denies for "!verify = sender". AFAICT this has not denied any spam that has come in, so at this point, I will probably disable it again. I enabled CHECK_RCPT_REVERSE_DNS, which warns if the reverse host lookup on the sender fails--and adds a X-Host-Lookup-Failed header. This seemed to mark much of the spam. I considered modifying it to use 'deny', instead of 'warn', but I'm concerned about false positives. Is there a better way to use CHECK_RCPT_REVERSE_DNS, either to deny at the rcpt level, or to utilize the X-Host-Lookup-Failed header that is placed on it? I have used SpamAssassin, but I wasn't getting the desired results before, so before I turn it on again, I would like to try to filter out as much at the mail server as possible. Thanks, Casey -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
