Bug ID 702457: DNS Cache connections remain open indefinitely

Last Modified: Aug 08, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP DNS, GTM, LTM(all modules)

Known Affected Versions:
12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 12.1.5, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.1, 13.1.1.2, 13.1.1.3, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4

Fixed In:
14.1.0, 14.0.0.5, 13.1.1.4

Opened: Jan 17, 2018
Severity: 3-Major

Symptoms

Resize / Clearing the DNS cache while a lot of traffic is running can cause numerous connections to remain open indefinitely. tmm crash

Impact

Connections remain open forever, using up memory

Conditions

Resize / Clear the DNS Cache while it is resolving connections.

Workaround

If you are encountering this, you can remove these connections by restarting tmm: tmsh restart sys service tmm Impact of workaround: Traffic disrupted while tmm restarts.

Fix Information

Fixed an issue where the DNS Cache kept connections open indefinitely when clearing or resizing a cache with active resolutions occurring.

Behavior Change