Bug ID 525958: TMM may crash if loadbalancing to node's IP in iRule routed towards an unreachable nexthop.

Last Modified: Aug 19, 2026

Affected Product(s):
BIG-IP All(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, 11.6.0, 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

Fixed In:
12.0.0, 11.6.1, 11.5.4

Opened: Jun 01, 2015

Severity: 3-Major

Related Article: K17187

Symptoms

In a specific combination of events TMM may core.

Impact

Traffic disrupted while tmm restarts.

Conditions

This occurs when the following conditions are met: - Load balancing a flow to an ip_tuple (e.g., the Tcl 'node' command). - That address is not directly connected. - The matched route is a gateway pool that contains a pool member that is not reachable.

Workaround

Ensure correct routing to all destinations with reachable next hops.

Fix Information

TMM no longer cores when load balancing to a node's IP address in iRule, routed towards an unreachable nexthop.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips