Bug ID 655448: Virtual Edition Single-process requirement not enforced

Last Modified: Jul 12, 2023

Affected Product(s):
BIG-IP MA-VE(all modules)

Known Affected Versions:
13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1

Fixed In:
13.1.0

Opened: Apr 05, 2017

Severity: 4-Minor

Related Article: K80470655

Symptoms

Although it is not a supported operation, a BIG-IP administrator can change the number of threads TMM runs per process by modifying the 'tmm.threads' db variable. Virtual Edition TMM code is written with the assumption that all TMMs run as threads in one TMM process, so modifying this variable can cause multi-process TMMs, which do not pass traffic. Running the following command doesn't display the dataplane interfaces for one or more TMMs: tmctl -f /var/tmstat/blade/tmm<x> -s name,if_index interface_stat

Impact

Some of the TMMs, though launched and running, do not pass traffic, resulting in degraded performance (throughput, CPS) for the assigned number of cores.

Conditions

When tmm.threads db variable is set a value other than 0 (the default value).

Workaround

Do not change the tmm.threads db variable from its default value of 0.

Fix Information

With this fix, any non-default value set to tmm.threads db variable is ignored.

Behavior Change

Guides & references

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