Installing and Administering Internet Services

168 Chapter4
Installing and Administering sendmail
Creating sendmail Aliases
two systems. sendmail adds a tracing header line (Received:) with each
hop. When 30 tracing header lines have been added, sendmail
recognizes the aliasing loop and aborts the delivery with an error
message.
Creating a Postmaster Alias
RFC 822 requires that a “postmaster” alias be defined on every host. The
postmaster is the person in charge of handling problems with the mail
system on that host.The default aliases file suppliedwith HP-UX defines
the postmaster to be root. You can change this alias to the appropriate
user for your system.
Verifying Your sendmail Aliases
After you have created a sendmail alias and regenerated the aliases
database, issue the following command to verify that your alias is valid:
/usr/sbin/sendmail -bv -v alias , alias , . . .
The -bv option causes sendmail to verify the aliases without collecting
or sending any messages. Any errors in the specified aliases will be
logged to standard output.
Users can use the HP expand_alias utility to expand an alias or mailing
list as far as is possible. For more information on the expand_alias
utility, type man 1M expand_alias at the HP-UX prompt.
Managing sendmail Aliases with NIS or NIS+
The sendmail aliases database can be managed through the Network
Information Service (NIS or NIS+), which is one of the NFS Services.
NIS or NIS+ allows you to maintain an aliases database on one server
system. All other systems request alias information from the server. In
order to use NIS or NIS+, you must set up an NIS or NIS+ domain and
configure the machines in your network as NIS or NIS+ servers and
clients. For information about the NIS or NIS+ aliases database, see
Installing and Administering NFS Services.
When you configure NIS or NIS+ in your network, it manages your
sendmail aliases by default, so you do not have to make any changes to
your NIS or NIS+ configuration.
Before you run the NIS ypinit script or the NIS+ nispopulate script,
make sure the /etc/mail/aliases file on the NIS or NIS+ master