Bug ID 1756397: BIG-IP is not forwarding the Extended DNS Error (EDE) Codes to Clients

Last Modified: Oct 15, 2025

Affected Product(s):
BIG-IP DNS(all modules)

Known Affected Versions:
17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3

Fixed In:
17.5.1

Opened: Nov 27, 2024

Severity: 3-Major

Symptoms

When BIG-IP processes responses from upstream name servers, it strips the Extended DNS Error (EDE) information, which provides additional details about the cause of DNS errors.

Impact

DNS clients will not receive additional information about the cause of DNS errors.

Conditions

-- BIG-IP is configured with a listener that has a DNS profile to process DNS queries. -- DNS requests from clients include the EDNS (Extension Mechanisms for DNS) flag.

Workaround

None

Fix Information

With the fix, BIG-IP is now able to process and respond to clients with Extended DNS Errors (EDE) information that it receives from upstream name servers. We have exposed the fix through a Db variable called dns.forwardextendeddnserrorcode. By default, the Extended DNS Errors(EDE) support is disabled. If you want to enable EDE support you can change the Db variable value to enable. sys db dns.forwardextendeddnserrorcode { value "enable" } To avoid truncation due to lengthy extra text that is part of the EDE, we have limited it to 64 bytes.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips