Open Relay Testing

These tools allow for the testing of a mail relay to see if it will relay third-party email.

• Web-based Relay Checkers
• Telnet Relay Checkers
• Scripts for Relay Testing
• Private Relay Testers
• Open Relay Testing Techniques
• Known Relay Testing Policies

Related

• Open Relays Blacklists
• Open Relays
• Open Relay Honeypots
• Open Proxy Tools

Web-based Relay Checkers

Relay testers for general use (as far as can be reasonably determined).

Abuse.net relay testing - www.abuse.net/relay.html
Open Relay Test - members.iinet.net.au/~remmie/relay/
Anonymous Relay Test - www.antispam-ufrj.pads.ufrj.br/test-relay.html
Anonymous Relay Test - www.aupads.org/test-relay.html
Third Party Relay Check - www.rbl.jp/svcheck.php
Open Relay Tester - www.mob.net/~ted/tools/relaytester.php3
SpamHelp.org SMTP Open Relay Test - www.spamhelp.org/shopenrelay/

Telnet Relay Checkers

Telnet to the server shown from the server you wish to test.

telnet relay-test.mail-abuse.org
telnet rt.njabl.org 2500

Script Relay Checkers

Scripts to test relays.

mrt - www.monkeys.com/mrt/ - Perl
rlytest - www.unicom.com/sw/rlytest/ - Perl
mtaprobe.exp - www.cymru.com/Tools/mtaprobe.exp - Expect
relaycheck.pl - arpa.org/relaycheck.pl - Perl
SMTP Open Relay Checker - sourceforge.net/projects/smtprc - FreeBSD
testrelay - www.kluge.net/~felicity/random/testrelay.txt - Perl
relaytest - ftp://ftp.ruhr-uni-bochum.de/local/mail/spamtools/relaytest - Perl
RelayTest - www.digiarch.org/relaytest.html - Win
SORBS - sorbs.sourceforge.net/ - checks incoming servers for open relays and proxies

Private Relay Checkers

Services for users in particular organizations.

JANET's STAN - www.ja.net/services/mail/janet-spam-relay-tester-and-notification-system.html
Tiscali UK Open Relay Scan - 212.74.112.52:6080/cgi-bin/request-check

Open Relay Testing Techniques

Discussion and the format for relay tests.

Relay Testing Envelopes - www.chebucto.ns.ca/~af380/envelopes.txt
Open Relay Verifying Engine Tests - www.aupads.org/working.html
Relay Testing Envelopes - www.ki.nu/software/sendmail/orbs-envelopes.shtml
Some open relay tests - www.reedmedia.net/misc/mail/open-relay.html
Relaying Methods - www.dsbl.org/relay-methods

Known Relay Testing Policies

MX Probe Data Base - mxdb.com/list/
Active tests of JANET mail relays - www.ja.net/services/mail/janet-spam-relay-tester-and-notification-system.html#unasked