Bug ID 628721: In rare conditions, DNS cache resolver outbound TCP connections fail to expire.

Last Modified: Jul 12, 2023

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

Known Affected Versions:
13.1.0, 13.0.0, 12.1.2, 12.1.1, 12.1.0, 12.0.0, 11.6.1, 11.6.0, 11.5.4, 11.5.3, 11.5.2, 11.5.1, 11.5.0

Fixed In:
13.1.0, 13.0.1,

Opened: Nov 15, 2016

Severity: 3-Major


If a TCP connection is initiated by the DNS cache resolver but fails to be fully created, it may be leaked until the next restart of tmm.


If enough connections are leaked, the tmm will not be able to create new connections even if the conditions causing the "hud_msg_queue" log messages resolve.


This is only known to occur when other internal issues are affecting the tmm's functionality. If there are ongoing log messages in the tmm logs of the form: "hud_msg_queue is full," and a DNS cache resolver is attempting new outbound TCP connections, then it is possible to leak these connections.


Restarting tmm will clear the leaked connections.

Fix Information

The connections are now properly cleaned up if they are unsuccessfully created.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips