Bug ID 424031: CGNAT: Deterministic Mode and using same LSN Pool with more than one VS

Last Modified: Apr 10, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP CGN(all modules)

Known Affected Versions:
11.3.0, 11.4.0

Fixed In:
11.5.0, 11.4.0 HF3, 11.3.0 HF8

Opened: Jun 26, 2013
Severity: 3-Major
Related AskF5 Article:
K14596

Symptoms

- Deterministic NAT translations are not using all the translation addresses and ports configured. - Run command dnatutil --action summary will display N times the number of subscribers

Impact

Only a fraction of the translation addresses and ports available will be used. If you have 2 virtual servers - 1/2 the translation space. 3 virtual servers - 1/3rd the space. This could result in more frequent translation failures if a there are not enough ports available to each subscriber.

Conditions

- LSN pool using deterministic mode - 2 or more virtual servers using this same LSN pool and the same source address range

Workaround

None

Fix Information

An issue was fixed where CGNAT in Deterministic NAT translations were not using all the translation addresses and ports configured.

Behavior Change