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Registration needed for mail servers to accept email from the Internet

Skip Navigation LinksHelp pages for mmmservices > Managing your Mailbox > Security > Registration needed for mail servers to accept email from the Internet


You may be concerned by this announcement only if you administer a mail server (sendmail, postfix etc.), it concerns mails sent from the Internet to addresses like
People managing mail servers are requested to register their machines in order to accept mails from outside CERN. The CERN mail infrastructure will relay messages coming from outside CERN only to mail servers that are registered. The rule applies only to messages that are sent from the Internet. There will be NO change for messages sent inside CERN.

There is a machine named “” running an SMTP server and accepting messages. If the account “johnsmith” on this machine wants to receive mails, they must be sent to
Consequently, if some non-CERN user (e.g. sends a mail to, this mail will be delivered ONLY if the server “” is registered in the CERN Mail System.

Please check current list of registered machines in LanDB ( Registered machines are members of set "MAIL ACCEPTING_FROM_INTERNET". To display content of the set choose: "Set Mgmnt" -> "Display set" -> specify name "MAIL ACCEPTING_FROM_INTERNET".

If you don’t find your machine on the list please contact the Helpdesk to register it.