Bug ID 556380: mcpd can assert on active connection deletion

Last Modified: Aug 19, 2026

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

Known Affected Versions:
11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.5.3, 11.5.3 hf1, 11.5.3 hf2, 11.5.4, 11.5.4 hf1, 11.5.4 hf2, 11.5.4 hf3, 11.5.4 hf4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8, 12.0.0, 12.0.0 hf1, 12.0.0 hf2, 12.0.0 hf3, 12.0.0 hf4

Fixed In:
12.1.0, 11.6.1

Opened: Nov 05, 2015

Severity: 2-Critical

Related Article: K13165903

Symptoms

When all of the peers in an HA / DSC configuration are removed, then it is possible for the connection tear down to result in an assert.

Impact

MCPD asserts and restarts.

Conditions

Removal of all peers while a connection is handling a transaction.

Workaround

No workaround is necessary. MCPD restarts.

Fix Information

Connection tear down checks for active connections and does not result in an assert when removing all peers while a connection is handling a transaction.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips