XBee3 disconnects endpoints

Hi! I have XBee3 as coordinator of my network. I have recently upgraded to 100A (but noticed the issue in 1009). The network consists of various xiaomi sensors, a xiaomi power relay (works as mains powered zigbee router), and other XBees, including XBee3 and S2C.

The issue is that some of my devices start leaving network after a while (several hours to several days).
It seems that the most affected devices are the endpoints that communicate directly to the coordinator. Routers are either not affected or affected much less. Endpoints that communicate via routers are also either affected less or not affected at all.

I’m sure some of the older firmwares work correctly. However when I’ve tried to downgrade the firmware to test I found it was impossible for some reason.

May be the issue is related to the fact that endpoints (sensors) are not sending any data very often. I have an illumination sensor that sends updates very often, and it works fine despite being an endpoint. At the same time a cube sensor, which only communicates when I interact with the device, is probably the first to disconnect. I will also try switch off one of the xbee3 routers for the experiment to check if it would lose the network or not.

US=0, C8=0x10, EE=1, EO=2, RK=0, DO=0x40, VR=100A, VH=181, HV=4247, R?=0.

Please advice. This must be a known issue!


You need to set the sleep times (SP, SN, SO) so that you are setting these timers to a greater sleep time than your longest end points sleep time. Not doing so can cause the end device to become disassociated.

Digi Support

Hi! Thank you for the suggestion! This period is already more than 4 hours, I will try to set it to maximum value, but it is probably already more than the weather sensors update their values. May I also ask you explain why it didn’t happen on older firmware and with endpoints that connect via routers?

This is only a guess as I don’t know what is causing the end devices to leave. It could be they are out of range or are missing poll requests. The best way to see why is to use a zigbee packet sniffer.

I’ve made some tests:

  1. I’ve powered off one of the routers (another xbee3) for about a day (longer than the period defined with SP and SN) and it reconnected to the network without a problem
  2. I’ve set SN to 0xFFFF, but my sensors keep loosing network.
  3. I am still sure I did not experience that with some older firmwares, but I am unable to downgrade it using OTA for some reason (is it another bug?)

There are security updates that now exists in the 0x0A code that keeps you from going back words.

I feel this needs to be sent to support via an email and case so it can be researched and answered.


Thank you, I will write to tech.support.

The Release Notes doesn’t warn the firmware cannot be downgraded OTA, so it looks like a bug.
But I was able do downgrade it with combination of ser2net and ttynvt, and tested with different firmware versions:
1006, 1007 and 1008 do not have this issue.
1009 and 100A have an issue
So it looks like a regression between 1009 and 1008.
I tested them with identical settings in a network with only the coordinator and two sensors.