IP Address Blocklist Check This server's IP xx.xx.xx.xx is on a blocklist. SpamHaus Zen

[DualOSWinWiz]

IP Address Blocklist Check Issue - False Positive on SpamHaus Zen

Issue Summary

I am experiencing an intermittent issue where Cloudron reports that my server's IP (xx.xx.xx.xx) is on a blocklist, specifically SpamHaus Zen. However, when I manually check on the SpamHaus website, my IP is not listed.

Environment Details

• Self-hosted Cloudron instance
• Unbound DNS service is running
• Firewall is not encrypting DNSSEC
• PTR (Reverse DNS) records are correctly configured

Observations

• The error disappears randomly at times, and Cloudron shows no issue.
• However, most of the time, the blocklist warning persists.
• PTR (reverse DNS) records are correctly set up and resolve fine.
• This seems to be an issue related to DNS resolution or Unbound's behavior rather than an actual blocklist listing.

Troubleshooting Steps Taken

1. Manually checked my IP on SpamHaus’s official website – IP is not listed.
2. Restarted Unbound to see if it helps resolve any DNS caching issue.
3. Verified PTR (Reverse DNS) records – confirmed they are properly configured.
4. Confirmed DNSSEC settings – firewall is not encrypting DNSSEC, so that shouldn’t be affecting the lookup.

Questions & Assistance Needed

• Has anyone else encountered similar false positive blocklist checks in Cloudron?
• Could Cloudron’s Unbound service be returning outdated/cached blocklist results?
• Any recommended steps to debug Unbound’s DNS resolution for blocklist lookups?

Any insights or suggestions would be greatly appreciated. Thanks in advance!

[jdaviescoates]

This sounds like that same issue as reported here https://forum.cloudron.io/post/102535

[DualOSWinWiz]

mine is happening randomly

[DualOSWinWiz]

This post is deleted!

[jdaviescoates]

@jdaviescoates said in URGENT:

In a post on an originally unrelated thread about IPv6 issues @Gengar posted this link https://www.spamhaus.com/resource-center/successfully-accessing-spamhauss-free-block-lists-using-a-public-dns/ which I think explains what's going on with all these false positive spamhaus issues people are having:

The TL;DR seems to be: fill in this form https://www.spamhaus.com/free-trial/sign-up-for-a-free-data-query-service-account/