This article provides information and solution for flowd core generated on 5K leading to outage.

The below core dumps will been seen during issue state-

user@router> show system core-dumps no-forwarding

-rw-r--r-- 1 root wheel 2070426295 Dec 16 11:11 /var/crash/core-SRX-hostA-fpc2.pic1-flowd_spc3.elf.0.tgz

This is a known issue on SRX5K series. The problem occurs when the SRX caches a next hop during packet reinjection, but the next hop becomes invalid before the reinjection completes due to large-scale Layer 2 flow changes, interface modifications, or route updates. This is more likely to occur in environments with a high number of configured interfaces, where next hop changes are frequent and complex. This issue can cause the PFE crash, leading to temporary traffic interruption.

The flowd process will respawn/restart automatically.

This issue is resolved in the following releases-

23.4R2-S5, 24.2R2-S2, 24.4R2, 25.2R1, 25.3R1

Fore more information, please refer to PR1856200.