Check if Mailing IP Blacklisted on VPS

Here we cover how to check if the IP used to send mail from a VPS is blacklisted on the most common blacklists. This process is used when emails are being marked as spam or you are seeing Spam/IP blocked. 

You could also see either of the following error codes:

550 high probability of spam   OR    554 Service unavailable; Client host [IP] blocked using [URL]

Check Mailing IP

NOTE: This will compare the IP against several major mail services for blacklisting.

1. SSH into the server
2. Run the command /opt/dedrads/msp.pl --rbl --all​​
3. Check the primary IP of the server hostname -i against the following blacklist-checking sites
   1. https://mxtoolbox.com/blacklists.aspx
   2. http://multirbl.valli.org/lookup/
   3. http://www.blacklistalert.org/
   4. http://www.anti-abuse.org/