When a Disk Is Full
Mail service becomes erratic if the disk storing your mail reaches maximum capacity. When your disk reaches full capacity, you’ll experience the following:
ÂÂ Postfix: If the operating system can still spawn the smtpd process, Postfix tries to function and attempts to accept the message. The message is then rejected with a “disk full” error. Otherwise, its behavior is unpredictable.
ÂÂ Dovecot: If the operating system can still spawn an imapd or pop3d process, the server attempts to open the user’s mail account. Upon success, the user can access mail as normal.
When Mail Is Undeliverable
Mail messages might be undeliverable for several reasons. Incoming mail might be undeliverable because it has a misspelled address or is addressed to a deleted user account. Outgoing mail might be undeliverable because it’s misaddressed or the destination mail server isn’t working.
You can configure Mail service to:
ÂÂ Forward undeliverable incoming mail
ÂÂ Limit the number of attempts to deliver problematic outgoing mail
ÂÂ Report failed delivery attempts
ÂÂ Use a different timeout value to increase the chance of connection success
Forwarding Undeliverable Incoming Mail
Mail service can forward messages that arrive for unknown local users to another real local person or a group in your organization. Whoever receives forwarded mail that’s incorrectly addressed (with a typo in the address, for example) can forward it to the correct recipient.
If forwarding of these undeliverable messages isn’t explicitly enabled, the messages are returned to sender.
To forward undeliverable mail, see “Unsubscribing from a Mailing List Via Web” on page 56.
Where to Find More Information
You can find more information about Mail service in books and on the Internet.
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Chapter 5 Troubleshooting Mail Service
