Domain Name System Blacklists (DNSBLs) are spam blocking lists which contain a number of IPs (mailserver IPs) which have been reported as sending out spam. Blocklisting happens for any number of reasons, most typically when an IP address is suspected of sending spam. Continual blocklisting will affect your IP reputation because your IP address will be identified as a regular source of spam.
Once you’re listed- as the name indicates- you’re “black-listed”- much of your email won’t be reaching its destination, and traffic to your websites could be limited. If your business relies on email - either as a tool, or a product- then the longer you’re listed, the worst it is for your bottom line, and your reputation. It looks really bad if your customers email you, and get a bounce message indicating that your email system has been blocked.
In summary, If your IP lands up there, you are doing something wrong... or something is wrong with your network configuration.
https://en.wikipedia.org/wiki/Domain_Name_System-based_Blackhole_List
This lists gov.uk domains from most if not all government agencys and which DNSBL's they appear on.
https://en.wikipedia.org/wiki/Comparison_of_DNS_blacklists https://www.spamhaus.org/faq/section/DNSBL%20Usage
output.csv - the list of gov.uk domains I am checking.
blacklist_domains.csv - the list of the ones that appear on the blacklist (you should start here and check if your agency is on there)
If you would like to contribute, Please let me know or raise an issue.
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