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
9 marketer 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
5 Jun 2024 - 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.
19 Nov 2022 - Webmaster Forum
What the experts say
2 expert 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.
3 Oct 2024 - 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.
14 Jan 2024 - Wordtothewise.com
What the documentation says
4 technical 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.
22 May 2024 - 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.
19 Jul 2024 - SURBL.org
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