Disney web site - otheruser@otherhost. You can think of this as an
otheruser@otherhost. You can think of this as an advanced mail alias feature, one that operates using not just the destination user, but also the destination domain. To configure the virtusertable feature, add the feature to your sendmail.mc configuration as shown: FEATURE(virtusertable) By default, the file containing the rules to perform translations will be /etc/mail/virtusertable. You can override this by supplying an argument to the macro definition; consult a detailed sendmail reference to learn about what options are available. The format of the virtual user table is very simple. The lefthand side of each line contains a pattern representing the original destination mail address; the righthand side has a pattern representing the mail address the virtual hosted address will be mapped to. The following example shows three possible types of entries: samiam@bovine.net colin sunny@bovine.net darkhorse@mystery.net @dairy.org mail@jhm.org @artist.org $1@red.firefly.com In this example, we are virtual hosting three domains: bovine.net, dairy.org, and artist.org. The first entry redirects mail sent to a user in the bovine.net virtual domain to a local user on the machine. The second entry redirects mail to a user in the same virtual domain to a user in another domain. The third example redirects all mail addressed to any user in the dairly.org virtual domain to a single remote mail address. Finally, the last entry redirects any mail to a user in the artist.org virtual domain to the same user in another domain; for example, julie@artists.org would be redirected to julie@red.firefly.com. Testing Your Configuration The m4 command processes the macro definition files according to its own syntax rules without understanding anything about correct sendmail syntax; so there won’t be any error messages if you’ve gotten anything wrong in your macro definition file. For this reason, it is very important that you thoroughly test your configuration. Fortunately, sendmail provides a relatively easy way of doing this. sendmail supports an “address test” mode that allows us to test our configuration and identify any errors. In this mode of operation, we invoke sendmail from the command line, and it prompts us for a ruleset specification and a destination mail address. sendmail then processes that destination address using the rules specified, displaying the output of each rewrite rule as it proceeds. To place sendmail into this mode, we invoke it with the -bt argument: # /usr/sbin/sendmail -bt ADDRESS TEST MODE (ruleset 3 NOT automatically invoked) Enter
> The default configuration file used is the /etc/mail/sendmail.cf file; you can specify an alternate configuration file using the -C argument. To test our configuration, we need to select a number of addresses to process that will tell us that each of our mail-handing requirements are met. To illustrate this, we’ll work through a test of our more complicated UUCP configuration shown in Example 18.2. First we’ll test that sendmail is able to deliver mail to local users on the system. In these tests we expect all addresses to be rewritten to the local mailer on this machine: # /usr/sbin/sendmail -bt ADDRESS TEST MODE (ruleset 3 NOT automatically invoked) Enter
> 3,0 isaac rewrite: ruleset 3 input: isaac rewrite: ruleset 96 input: isaac rewrite: ruleset 96 returns: isaac rewrite: ruleset 3 returns: isaac rewrite: ruleset 0 input: isaac