Installing and Administering Internet Services

186 Chapter4
Installing and Administering sendmail
Modifying the Default sendmail Configuration File
recipient addresses are to be interpreted.
• Defines the delivery agents (mailers) to be used for delivering the
mail.
• Specifies how sendmail should rewrite addresses in the header, if
necessary, so that the message address can be understood by the
receiving host. The address rewriting process is controlled by sets of
address rewriting rules called “rulesets.”
Restarting sendmail
• Issue the following commands, on a standalone system or on the mail
server, to restart sendmail:
/sbin/init.d/sendmail stop
/sbin/init.d/sendmail start
You must restart sendmail if changes are made to any of the following:
• The sendmail configuration file, /etc/mail/sendmail.cf.
• The UUCP configuration, as reflected in the output of the uuname
command.
Forwarding Non-Domain Mail to a Gateway
Mail that is being sent to a domain other than the sender’s domain can
be forwarded to a mail gateway. To have non-domain mail forwarded to a
mail gateway, edit the DS line in the /etc/mail/sendmail.cf file to
specify the host name of the mail gateway:
DSmailgw.cup.hp.com
Configuration Options
The sendmail configuration options to set mail header lengths and limit
message recipients have been added or enhanced.
Setting Mail Header Lengths
You can set a limit for the mail header. The maximum header length by
default is 32768. To change the mail header length:
• Open the sendmail.cf file, then set the value of the option
MaxHeadersLength=n, where n is the maximum number of lines