Hello all. I decided to upgrade my sonoff dongle E to a ZBT-2 and to recreate my network from scratch. Before everything was working okay, but now I am encountering a weird issue when trying to pair a device.
I fully resetted my ikea ceiling light and allowed joining in the z2mqtt app ( i have everything running in docker ). The light won’t pair, and after the timer runs out or i cancel the allow pair, i get these logs and the z2mqtt container restarts:
[2026-01-04 23:15:37] info: z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/response/permit_join', payload '{"data":{"time":254},"status":"ok","transaction":"ysqek-1"}'
[2026-01-04 23:18:29] info: z2m: Zigbee: disabling joining new devices.
[2026-01-04 23:18:29] error: zh:ember:uart:ash: Received ERROR from adapter, with code=ERROR_EXCEEDED_MAXIMUM_ACK_TIMEOUT_COUNT.
[2026-01-04 23:18:29] error: zh:ember:uart:ash: ASH disconnected | Adapter status: ASH_NCP_FATAL_ERROR
[2026-01-04 23:18:29] error: zh:ember:ezsp: Fatal error, status=ASH_NCP_FATAL_ERROR. Last Frame: [FRAME: ID=54:"SEND_BROADCAST" Seq=38 Len=7]
[2026-01-04 23:18:29] info: zh:ember:uart:ash: ASH COUNTERS since last clear:
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Total frames: RX=48, TX=87
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Cancelled : RX=0, TX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: DATA frames : RX=44, TX=40
[2026-01-04 23:18:29] info: zh:ember:uart:ash: DATA bytes : RX=413, TX=464
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Retry frames: RX=0, TX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: ACK frames : RX=0, TX=45
[2026-01-04 23:18:29] info: zh:ember:uart:ash: NAK frames : RX=2, TX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: nRdy frames : RX=0, TX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: CRC errors : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Comm errors : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Length < minimum: RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Length > maximum: RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Bad controls : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Bad lengths : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Bad ACK numbers : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Out of buffers : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Retry dupes : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Out of sequence : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: ACK timeouts : RX=0
[2026-01-04 23:18:29] info: zh:ember:uart:ash: Port closed, error=null
[2026-01-04 23:18:29] info: zh:ember:uart:ash: ======== ASH stopped ========
[2026-01-04 23:18:29] info: zh:ember:ezsp: ======== EZSP stopped ========
[2026-01-04 23:18:29] info: zh:ember: ======== Ember Adapter Stopped ========
[2026-01-04 23:18:29] error: z2m: Adapter disconnected, stopping
[2026-01-04 23:18:44] error: zh:ember:ezsp: ERROR Transaction failure; status=ASH_ERROR_TIMEOUTS. Last Frame: [FRAME: ID=54:"SEND_BROADCAST" Seq=38 Len=7].
[2026-01-04 23:18:44] error: z2m: Request 'zigbee2mqtt/bridge/request/permit_join' failed with error: 'ASH_ERROR_TIMEOUTS'
[2026-01-04 23:18:44] info: z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/response/permit_join', payload '{"data":{},"error":"ASH_ERROR_TIMEOUTS","status":"error","transaction":"salu0-1"}'
[2026-01-04 23:19:38] info: z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/state', payload '{"state":"offline"}'
[2026-01-04 23:19:38] info: z2m: Disconnecting from MQTT server
[2026-01-04 23:19:38] info: z2m: Stopping zigbee-herdsman...
[2026-01-04 23:19:38] info: z2m: Stopped zigbee-herdsman
[2026-01-04 23:19:38] info: z2m: Stopped Zigbee2MQTT
Using '/app/data' as data directory
Starting Zigbee2MQTT without watchdog.
I debugged this hours on end with ChatGPT and the internet in general, but i found nothing that worked.
The z2mqtt serial configuration is this:
serial:
port: /dev/ttyACM0
baudrate: 460800
adapter: ember
rtscts: true
