SORBS DUHL

dul.dnsbl.sorbs.netIP blocklistSORBS (Proofpoint) ↗
Removal
Request with rDNS proof
Cost
Free
Time to clear
Reviewed

About SORBS DUHL

The DUHL flags IPs that appear to be dynamically assigned (home/DSL/cable style). Mail servers are expected to live on static IPs with proper naming, so a DUHL hit usually means your rDNS looks generic.

Why an IP gets listed

  • The IP’s reverse DNS looks dynamic/auto-generated (e.g. contains the IP or “dynamic”/“dhcp”).
  • The range is registered as dynamic by the ISP.

How to delist from SORBS DUHL

  1. 1Set a proper static PTR record for the mail server (your host/ISP controls this).
  2. 2Ensure forward and reverse DNS match.
  3. 3Request DUHL delisting via SORBS support, noting the IP is static and correctly named.
Open SORBS DUHL lookup / removal page ↗
Before you request removal: fix the root cause first — delisting while the problem persists almost always leads to a fast re-listing. Confirm the IP has valid reverse DNS, and that your SPF, DKIM and DMARC are in order.

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