Bug ID 1317773: CGNAT / AFM NAT: "Clients Using Max Port Blocks" counter might be inaccurate

Last Modified: Dec 28, 2023

Affected Product(s):
BIG-IP AFM, CGN(all modules)

Known Affected Versions:
15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1

Opened: Jul 07, 2023

Severity: 4-Minor

Symptoms

When using CGNAT or AFM NAT in PBA mode (Port Block Allocation) the value of "Clients Using Max Port Blocks" might be wrong, not reflecting the actual number of total clients who have reached the max port blocks allocated to them. The value of "Clients Using Max Port Blocks" can be seen in the output of the command "tmsh show ltm lsn" along with other statistics.

Impact

The value of "Clients Using Max Port Blocks" is increased when clients reach the max port blocks allocated to them but is not decreased when the clients don't have any more port blocks allocated. As such, it keeps increasing over time.

Conditions

- BIG-IP running two or more TMM threads - BIG-IP provisioned with CGNAT or AFM NAT - LSN pool using PBA (Port Block Allocation) configured

Workaround

None

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips