Bug ID 953393: TMM crashes when performing iterative DNS resolutions.

Last Modified: Oct 21, 2020

Bug Tracker

Affected Product:  See more info
BIG-IP All(all modules)

Known Affected Versions:
14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 16.0.0, 16.0.0.1

Opened: Oct 08, 2020
Severity: 1-Blocking

Symptoms

TMM crashes and produces a core file.

Impact

Traffic disrupted while tmm restarts.

Conditions

The BIG-IP system configuration includes a Network DNS Resolver, which is referenced by another object (for example, a HTTP Explicit Forward Proxy profile) for DNS resolution.

Workaround

You may be able to work around this issue by having the Network DNS Resolver work in forwarding/recursive mode rather than in resolving/iterative mode. To do so, you configure a Forward Zone in the Network DNS Resolver for '.' (the DNS root). This causes DNS to send all DNS requests to a different, external resolver of your choice, which will perform recursive resolution. The servers you configure for the '.' Forward Zone could be resolvers internal to your organization or public resolvers (e.g. Google DNS).

Fix Information

None

Behavior Change