Andrew McDonough

Please note: This page is imported from my wiki, which hasn't been updated in over 10 years. Some of the formatting was lost during the import. I'll try to get around to fixing it someday.


Configuration files

A lot of sendmail’s configuration files are held in a database structure which has a binary format. The text versions of these files can be edited and then the databases rebuilt using the makemap command. For example, to rebuild the virtusertable database: /usr/sbin/makemap hash virtusertable.db <virtusertable


Mail servers should be configured so they are not ‘open relay’. IP addresses that are allowed to relay are specified in the access database. The text version of the database (/etc/mail/access) is in the format: RELAY When changed, the access database should be rebuilt: /usr/sbin/makemap hash access.db <access

Virtual Users Table

/usr/sbin/makemap hash virtusertable.db <virtusertable


Sendmail logs are usually kept in /var/log/mail. The info log gives information on any mail passing through the system. It is of the format:

sendmail[pid]: : =

Where qid = queue id

Andrew McDonough

Andrew McDonough is a consultant CTO and software developer, currently based between Berlin and London.

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