Bug ID 1099529: Tcpdump erroring out with errbuf ERROR:Session expired due to timeout

Last Modified: Oct 19, 2025

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

Known Affected Versions:
15.1.6, 15.1.6.1, 15.1.7, 15.1.8, 15.1.8.1, 15.1.8.2, 15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 15.1.10.5, 15.1.10.6, 15.1.10.7, 15.1.10.8, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3, 17.5.1, 17.5.1.2, 17.5.1.3

Opened: Apr 14, 2022

Severity: 3-Major

Symptoms

On a busy system, tcpdump may error out with the following error message: errbuf ERROR:Session expired due to timeout

Impact

Tcpdump may exit with an error message.

Conditions

-- Busy system -- BIG-IP Virtual Edition -- An F5OS tenant running on r2000k or r4000k -- A tcpdump filter that is logging a large amount of traffic

Workaround

Adjust the filter string to not capture as much traffic. Use the tmm.tcpdump.pkt.ratelimit db key to rate limit tcpdump traffic.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips