HP-UX Mailing Services Administrator's Guide (B2355-91064)
Mail sent to dave at either host sage or host basil bounces between the two systems.
Sendmail adds a tracing header line (Received:) with each hop. When 26 tracing
header lines have been added, Sendmail recognizes the aliasing loop and aborts the
delivery with an error message.
Creating a Postmaster Alias
RFC 2822 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 supplied with the HP-UX operating system designates the postmaster
as 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 the validity of your alias:
/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 are logged to standard output.
You can use the HP expand_alias utility to expand an alias or mailing list as far as
possible. For more information on the expand_alias utility, type man 1M
expand_alias at the HP-UX prompt.
Managing Sendmail Aliases with NIS
You can manage the Sendmail aliases database through the Network Information
Service (NIS), which is one of the NFS Services. This service 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, you must set up an NIS domain and configure the
machines in your network as NIS servers and clients. For information about the NIS
aliases database, see NIS Administrator's Guide at:
http://docs.hp.com/en/netcom.html.
When you configure NIS on your network, it manages your Sendmail aliases by default,
so you do not have to make any changes to your NIS configuration.
Before you run the NIS ypinit script, ensure that the /etc/mail/aliases file on
the NIS master server contains all the Sendmail aliases that you want to make globally
available through NIS.
The Sendmail program uses the Name Service Switch to determine where to look for
Sendmail aliases.
64 Configuring and Administering Sendmail