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Hello, I have a problem in receiving some of the mailing list messages. Some are accepted by the mail server I use, others are not and thus bounced. If some messages have been bounced, mail delivery is disabled for me until I manually reenable it. I have asked the administrator of the mail server I use why some messages are bounced and others are not. I got this explanation: There is an anti-spam appliance in front of the mail server which does forward and reverse DNS lookups and compares the result. $ host 213.132.101.140 140.101.132.213.in-addr.arpa domain name pointer www.crux.nu. 140.101.132.213.in-addr.arpa domain name pointer crux.nu. 140.101.132.213.in-addr.arpa domain name pointer mail.crux.nu. $ host www.crux.nu www.crux.nu is an alias for crux.nu. crux.nu has address 213.132.101.140 crux.nu mail is handled by 20 mx-gtw4.dnsnoc.net. crux.nu mail is handled by 10 mx-gtw1.dnsnoc.net. crux.nu mail is handled by 10 mx-gtw2.dnsnoc.net. crux.nu mail is handled by 20 mx-gtw3.dnsnoc.net. $ host crux.nu crux.nu has address 213.132.101.140 crux.nu mail is handled by 10 mx-gtw1.dnsnoc.net. crux.nu mail is handled by 10 mx-gtw2.dnsnoc.net. crux.nu mail is handled by 20 mx-gtw3.dnsnoc.net. crux.nu mail is handled by 20 mx-gtw4.dnsnoc.net. $ host mail.crux.nu Host mail.crux.nu not found: 3(NXDOMAIN) As solution he has given two alternate options: 1. Remove the reverse mapping to mail.crux.nu 2. Add a forward mapping for mail.crux.nu The reason why the comparison of the forward mapping and reverse mapping fails is and thus some mails are bounced is the inconsistency for the host mail.crux.nu. Is it possible to apply one of the two options so that I will receive all Crux mailing listing mails? I am tired of searching the mailing list archive for messages I have missed. Thanks, Markus Heinz