Cronjob an RBL Check

There’s a fantastic website that you can run curl to fetch a list of the blacklist and simple mail checks to ensure any of your servers that send mail aren’t blacklisted.

Create a new file at /etc/cron.daily/rblchecker and place these contents in:


Then make it executable chmod +x /etc/cron.daily/rblchecker and it’ll run. You may need to adjust the path to curl. When it runs, you’ll get the following output:

=================================== - Comments, suggestions and bug reports:

RBL Checks

  • not listed in Backscatterer
  • not listed in Barracuda Central
  • not listed in McAfee
  • not listed in SenderScore
  • not listed in SpamCop
  • not listed in SpamHaus PBL
  • not listed in SpamHaus SBL
  • not listed in SpamHaus XBL
  • not listed in UCE-Protect

Reverse Record Check

Reverse Record present:

SMTP port check

Connected to on port 25, mail banner says:
Found ‘A’ Record for
DNS ‘A’ record for matches the given IP


GOOD: Reverse record matches SMTP banner, 3-way mailcheck PASS.