Hi,
I’m observing an issue in a Zigbee network where, after several hours of correct operation, the routers stop retransmitting the NWK broadcast frames sent by the coordinator.
I’m attaching two captures:
-
Jun17_no_broadcasting.pcapng → The problem is already present.
-
Jun17_after_power_cycle.pcapng → After power‑cycling one router, retransmissions resume normally
The network key (to decrypt traffic) is: 0x00000000000000000000000000001234
What I am seeing in the capture
To view the broadcasts sent by the coordinator (NWK source 0x0000, destination 0xFFFF), I use the filter (zbee_nwk.src == 0x0000) && (zbee_nwk.dst == 0xffff)
I can see 355 broadcast frames from the coordinator.
To view the retransmissions that routers should perform, I use the filter ((zbee_nwk.src == 0x0000) && (zbee_nwk.dst == 0xffff)) && !(wpan.src16 == 0x0000)
This should show all routers forwarding those broadcasts. However, I see none.
It looks like all routers have stopped forwarding NWK broadcasts.
If I power‑cycle one router, the problem disappears immediately: that router starts retransmitting broadcasts again. This behavior is visible in the second capture.
Network setup
1 coordinator (DIGI)
8 routers (all nRF54L15)
Two routers are physically very close to the coordinator
No Trust Center (distributed security)
Zigbee R23 Add‑on v1.3.0
nRF Connect SDK v2.9.2
Multiprotocol option enabled, but BLE is currently disabled
NOTE: Same Zigbee application running on nRF52840 (Zigbee R22) works perfectly; we migrated to nRF54L15 because nRF52840 is not recommended for new designs, but we are facing several issues on the new platform.
Questions:
Is this a known issue with the Zigbee R23 Add‑on or with the nRF54L15 platform?
Are there any known conditions where routers may stop forwarding NWK broadcasts?
Is there any recommended workaround or configuration to avoid this behavior?
Could this be related to multiprotocol support even if BLE is disabled?
Any debugging steps you recommend to identify why routers stop retransmitting?
Thanks in advance.
Jun17_no_broadcasting.pcapngJun17_after_power_cycle.pcapng