Suped

Why does SURBL form say 'Lookup and requested host do not match'?

9 Marketer opinions2 Expert opinions4 Technical articles2 Resources

Summary

The 'Lookup and requested host do not match' error on the SURBL form is generally caused by a discrepancy between the hostname submitted for delisting and the actual hostname or IP address that SURBL has listed. This often happens when the root domain is submitted instead of a specific subdomain or URL, or when there are inconsistencies in DNS records, dynamic IPs, or CDN configurations causing IP mismatches. Other contributing factors include running a web server or scripts directly on the root domain and misunderstanding what the SURBL form is requesting. Accurate information submission, correct hostname/URL identification, and DNS record verification are key to resolving this error.

Key findings

  • Hostname Mismatch: Submitting the root domain instead of the specific subdomain or URL listed by SURBL is a common cause.
  • DNS/IP Inconsistencies: Discrepancies between current DNS records/IP addresses and those recorded by SURBL can trigger the error.
  • Dynamic IPs: Dynamic IP addresses might not match the IP recorded at the time of the listing.
  • CDN Issues: CDN configurations can cause IP mismatches.
  • Root Domain Scripts: Running web servers/scripts on the root domain can cause listings.
  • Information Accuracy: Errors in the submission form can cause a mismatch

Key considerations

  • Check Server Logs: Examine server logs to identify the specific hostname/URL flagged by SURBL.
  • Verify DNS Records: Ensure DNS records are accurate and consistent.
  • Submit Specific Hostname: Submit the exact hostname/URL listed by SURBL.
  • Investigate Compromised Scripts: Look for compromised scripts/subdomains sending spam.
  • Review CDN Configuration: Check CDN settings for correct IP resolution.
  • IP Address Fluctuation: Check if you are running a dynamic IP, this may not be the IP blacklisted.
  • Alternative Browsers: Consider trying a different browser to rule out form issues.
  • Identify the blacklisted Host: Ensure to find out what host got blacklisted.

What email marketers say
9Marketer opinions

The error 'Lookup and requested host do not match' on the SURBL form generally indicates a mismatch between the hostname submitted for delisting and the actual hostname listed by SURBL. This often occurs because SURBL lists specific subdomains or URLs implicated in spam activity, rather than entire root domains. Causes include submitting the root domain instead of a specific subdomain, inconsistencies in DNS records, dynamic IPs, CDN configurations causing IP mismatches, and running web servers or scripts on the root domain.

Key opinions

  • Hostname Mismatch: The primary reason is submitting the root domain instead of the specific subdomain or URL listed by SURBL.
  • DNS Inconsistencies: Incorrect or outdated DNS records can cause a mismatch between the submitted hostname and the resolving IP address.
  • Dynamic IPs: Dynamic IP addresses might not match the recorded IP at the time of the listing.
  • CDN Issues: Using a CDN can result in IP address mismatches if the CDN's IP is different from the origin server's IP.
  • Root Domain Scripts: Running a web server or scripts directly on the root domain can trigger automated listings.

Key considerations

  • Check Server Logs: Examine mail server logs to identify the exact hostname or URL being flagged by SURBL.
  • Verify DNS Records: Ensure that DNS records are accurate and consistent with the current IP address.
  • Submit Specific Hostname: Use the exact hostname or URL listed by SURBL in the delisting request.
  • Investigate Compromised Scripts: Look for compromised scripts or subdomains that may be sending spam.
  • Review CDN Configuration: Check CDN settings to ensure proper IP address resolution.
  • Webserver running on domain: If you are running a webserver on the primary domain or not.
Marketer view

Email marketer from Email Client Help Forum advises to double-check that the domain isn't a subdomain that got blacklisted and if your IP is dynamic it may not match the record now

September 2022 - Email Client Help Forum
Marketer view

Email marketer from Webmaster Forum mentions that they encountered the same issue and resolved it by checking their mail server logs. They found the exact hostname being flagged by SURBL was different from their primary domain and used that hostname in the removal request form.

April 2023 - Webmaster Forum
Marketer view

Email marketer from AskReddit advises they had this same issue and it was because their website was using a CDN that was causing a mis-match of IPs.

April 2024 - AskReddit
Marketer view

Marketer from Email Geeks asks to share the domain name being checked, and offers to huddle to share screens.

April 2023 - Email Geeks
Marketer view

Email marketer from Reddit suggests ensuring the hostname you are submitting matches the one that triggered the SURBL listing. Often, compromised scripts or subdomains can cause listings, rather than the main website, so check server logs for outgoing mail.

June 2021 - Reddit
Marketer view

Marketer from Email Geeks asks if the user is checking for a domain name or an IP address to troubleshoot the SURBL form issue.

September 2022 - Email Geeks
Marketer view

Email marketer from StackExchange suggests that the issue might stem from trying to remove a domain that isn't directly listed. SURBL often lists specific subdomains or hostnames responsible for spam, rather than entire domains. You need to identify the exact hostname listed to request removal.

August 2022 - StackExchange
Marketer view

Email Marketer from Email Geeks explains that the issue was misunderstanding point 6 which refers to the website domain which is actually listed and used for image hosting.

July 2021 - Email Geeks
Marketer view

Email marketer from EmailMarketingTips suggests to make sure that you are not running a webserver on the domain in question. A lot of the automated listings come from servers which look for php or other scripts responding on the root domain.

April 2022 - EmailMarketingTips

What the experts say
2Expert opinions

The 'Lookup and requested host do not match' error in SURBL forms often indicates that the system has blacklisted a specific subdomain or URL associated with spam, rather than the entire domain. It can also stem from inaccuracies in the submitted information, misaligned DNS records or IP addresses, or issues with the form itself. Confirming the exact problematic URL, verifying DNS records and IP alignment, and potentially trying a different browser are recommended steps to resolve the issue.

Key opinions

  • Specific URL Listing: SURBL typically lists a specific URL or subdomain responsible for spam, not the entire domain.
  • Information Accuracy: The information submitted to the SURBL form needs to be accurate.
  • DNS and IP Alignment: DNS records and IP addresses must align with the listing.
  • Potential Form Issues: Problems may reside with the form itself or a browser incompatibility.

Key considerations

  • Pinpoint Problematic URL: Identify the exact URL or subdomain causing the blacklisting.
  • Verify Information: Ensure all information submitted to the SURBL form is accurate.
  • Confirm DNS and IPs: Verify DNS records and IP addresses match the listed information.
  • Try Alternative Browser: Use a different browser to rule out browser-specific issues with the form.
Expert view

Expert from SpamResource.com explains the error often arises because the system identifies a specific subdomain or URL within the domain as the source of spam, not the root domain itself. The delisting request needs to pinpoint the exact problematic URL.

May 2022 - SpamResource.com
Expert view

Expert from Wordtothewise.com says the error 'Lookup and requested host do not match' occurs when there's an issue with the accuracy of the information you're submitting to the SURBL form or with the form itself. It is recommended to confirm DNS records and IP addresses align, and to try an alternative browser if problems persist.

January 2025 - Wordtothewise.com

What the documentation says
4Technical articles

The error 'Lookup and requested host do not match' on SURBL forms arises primarily due to inconsistencies between the hostname submitted for delisting and the actual hostname/IP address recorded by SURBL. This often involves submitting the root domain when a specific subdomain is listed, or discrepancies between current DNS records and the historical record at the time of listing. Using tools like `dig` or `nslookup` to diagnose DNS issues and ensuring the exact listed hostname is submitted are crucial for resolution.

Key findings

  • Hostname Alignment: The submitted hostname must precisely match the hostname listed by SURBL.
  • DNS Record Consistency: Inconsistencies between current DNS records and the historical IP recorded by SURBL cause the error.
  • Subdomain Listing: SURBL often lists specific subdomains rather than entire domains.

Key considerations

  • Verify Hostname: Confirm that the exact hostname listed by SURBL is used in the delisting request.
  • Check DNS Records: Verify DNS records are consistent and match the expected IP address.
  • Use Diagnostic Tools: Employ tools like `dig` or `nslookup` to identify DNS discrepancies.
  • Pinpoint Specific Subdomain: Identify the precise subdomain causing the listing if multiple subdomains exist.
Technical article

Documentation from MultiRBL states that the error message is usually caused by inconsistencies between DNS records and what the SURBL database has recorded. They recommend using a tool like `dig` or `nslookup` to diagnose DNS discrepancies.

August 2022 - MultiRBL.valli.org
Technical article

Documentation from SURBL.org states the error can occur if there are discrepancies between the resolved IP of your hostname at the time of listing and the IP currently resolving. Verify your DNS records are consistent and that the correct hostname is submitted.

March 2021 - SURBL.org
Technical article

Documentation from SURBL.org explains that the error 'Lookup and requested host do not match' typically occurs when the hostname used in the form doesn't align with the hostname that SURBL's systems have associated with the listing. Ensure that the exact hostname listed is used, not just the domain name.

November 2023 - SURBL.org
Technical article

Documentation from URIBL.com explains that 'Lookup and requested host do not match' means the hostname you're trying to delist wasn't the one actually blacklisted. This occurs frequently if there are multiple subdomains, and only one is the source of issues, so find the exact one triggering the blacklist.

December 2024 - URIBL.com

Related resources
2Resources

[resolver] failed to read from DNS server: ... i/o timeout - mailcow ...
[resolver] failed to read from DNS server: ... i/o timeout - mailcow ...

Hello, i have updated 2 of my mailcow installations to 2023-02a and now i got the following messages from one of them. Feb 23 15:07:41 mail01 dockerd[1861]...

mailcow community
Broken after reboot · Issue #2867 · Mailu/Mailu · GitHub
Broken after reboot · Issue #2867 · Mailu/Mailu · GitHub

Environment & Version Environment docker compose Version Version: 1.9 and 2.0 Description I've been running mailu for like two years now, from a mystery version to 1.7, to 1.9. During routine maint...

GitHub

Related questions