Bug ID 849157: An outgoing SCTP connection that retransmits the INIT chunk the maximum number of times does not expire and becomes stuck

Last Modified: Sep 13, 2023

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

Known Affected Versions:
15.0.0, 15.0.1,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,

Fixed In:
16.0.0, 15.1.4

Opened: Nov 12, 2019

Severity: 3-Major


The outgoing SCTP connection does not expire after attempting to INIT the maximum number of times. It then becomes stuck and does not expire when it reaches its idle-timeout, and cannot be manually deleted.


Stale SCTP connections are left in the system and start to use up memory. Traffic may be interrupted in certain configurations, as the system thinks it is still attempting to bring up the lost SCTP connection and does not ever try to create a new one.


An outgoing SCTP connection is permitted to attempt the INIT retransmit the maximum number of times configured with no responses (accepting or aborting) from the target endpoint.


To clear the stale connections, restart tmm: bigstart restart tmm Note: Restarting tmm causes an interruption to traffic.

Fix Information

SCTP connections now expire properly after the maximum number of INITs have been attempted and can no longer get stuck in this case.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips