The rlytest utility tests a host to determine whether it will relay third-party email. It will try to relay an email message to yourself through that host. A host that allows third-party relay is subject to attack by Internet vandals, and frequently is hijacked by spammers to relay massive amounts of junk email. A host that allows third-party relay should be immediately secured, disconnected, or shunned as a menace to the Internet.
This utility is a perl script. It requires Perl version 5.002 or above plus the IO::Socket module. This module is distributed with the core Perl 5.004 package, and is an add-on option for earlier versions.
Version 1.22 (22-Oct-2001) - Minor revisions to the text of the probe email message.
Version 1.21 (22-Oct-2001) - Corrected the outdated URLs in the probe email message.
Version 1.20 (21-Jun-2001) - Produce useful diagnostic if socket fails.
Version 1.19 (11-Jun-2001) - Now uses exit status 2 to indicate successful relay submission.
Version 1.18 (04-Apr-2001) - Changed default domain to example.com.
Version 1.17 (20-Aug-2001) - Fixed problem with uid=0 check.
Version 1.16 (25-May-2001) - Added guard against running as root. Simplified socket() error message.