OTBR error - Failed to perform next registration and mDNSPlatformSendUDP got error 99

retel · June 22, 2025, 9:16pm

Hi,

I’m having trouble setting up my Matter via Thread network. I’m running the latest version of HA 2026.6.1 using Home Assistant OS. I have the original Skyconnect device that have never been used before and I plugged it in, selected Thread. That installed the Open Thread Border Router and Thread integrations installed.

The Thread integration has a Preferred network set that is Home Assistant. Open Thread Border Router is configured like this:

I have two add-ons installed. Matter Server and the OpenThread Border Router. I’m unable to commission my first device (A smart lock by Secuyou) and I think the OTBR is the problem, because I see this in the logs:

-----------------------------------------------------------
 Add-on: OpenThread Border Router
 OpenThread Border Router add-on
-----------------------------------------------------------
 Add-on version: 2.13.0
 You are running the latest version of this add-on.
 System: Home Assistant OS 15.2  (amd64 / generic-x86-64)
 Home Assistant Core: 2025.6.1
 Home Assistant Supervisor: 2025.05.5
-----------------------------------------------------------
 Please, share the above information when looking for help
 or support in, e.g., GitHub, forums or the Discord chat.
-----------------------------------------------------------
s6-rc: info: service banner successfully started
s6-rc: info: service universal-silabs-flasher: starting
[22:57:50] INFO: Checking /dev/ttyUSB0 identifying SkyConnect v1.0 from Nabu Casa.
[22:57:50] INFO: Starting universal-silabs-flasher with /dev/ttyUSB0
2025-06-22 22:57:54.596 homeassistant universal_silabs_flasher.flash INFO Extracted GBL metadata: NabuCasaMetadata(metadata_version=2, sdk_version='4.4.4', ezsp_version=None, ot_rcp_version='SL-OPENTHREAD/2.4.4.0_GitHub-7074a43e4' (2.4.4.0), cpc_version=None, fw_type=<FirmwareImageType.OPENTHREAD_RCP: 'openthread_rcp'>, fw_variant=None, baudrate=460800)
2025-06-22 22:57:54.597 homeassistant universal_silabs_flasher.flasher INFO Probing ApplicationType.GECKO_BOOTLOADER at 115200 baud
2025-06-22 22:57:56.644 homeassistant universal_silabs_flasher.flasher INFO Probing ApplicationType.SPINEL at 460800 baud
2025-06-22 22:57:57.791 homeassistant universal_silabs_flasher.flasher INFO Detected ApplicationType.SPINEL, version 'SL-OPENTHREAD/2.4.4.0_GitHub-7074a43e4' (2.4.4.0) at 460800 baudrate (bootloader baudrate None)
2025-06-22 22:57:57.792 homeassistant universal_silabs_flasher.flash INFO Firmware version 'SL-OPENTHREAD/2.4.4.0_GitHub-7074a43e4' (2.4.4.0) is flashed, not re-installing
s6-rc: info: service universal-silabs-flasher successfully started
s6-rc: info: service otbr-agent: starting
[22:57:59] INFO: Setup OTBR firewall...
[22:58:00] INFO: Starting otbr-agent...
[NOTE]-AGENT---: Running 0.3.0-b067e5ac-dirty
[NOTE]-AGENT---: Thread version: 1.3.0
[NOTE]-AGENT---: Thread interface: wpan0
[NOTE]-AGENT---: Radio URL: spinel+hdlc+uart:///dev/ttyUSB0?uart-baudrate=460800&uart-flow-control
[NOTE]-AGENT---: Radio URL: trel://enp1s0
[NOTE]-ILS-----: Infra link selected: enp1s0
49d.17:03:42.829 [C] P-SpinelDrive-: Software reset co-processor successfully
00:00:00.066 [N] RoutingManager: BR ULA prefix: fd44:ac40:ff7a::/48 (loaded)
00:00:00.066 [N] RoutingManager: Local on-link prefix: fd55:1837:e819:d976::/64
00:00:00.102 [N] Mle-----------: Role disabled -> detached
00:00:00.135 [N] P-Netif-------: Changing interface state to up.
00:00:00.162 [W] P-Netif-------: Failed to process request#2: No such process
00:00:00.163 [W] P-Netif-------: Failed to process request#6: No such process
s6-rc: info: service otbr-agent successfully started
s6-rc: info: service otbr-agent-configure: starting
Done
s6-rc: info: service otbr-agent-configure successfully started
s6-rc: info: service otbr-agent-rest-discovery: starting
00:00:00.747 [W] P-Daemon------: Failed to write CLI output: Broken pipe
[22:58:01] INFO: Successfully sent discovery information to Home Assistant.
s6-rc: info: service otbr-agent-rest-discovery successfully started
s6-rc: info: service legacy-services: starting
s6-rc: info: service legacy-services successfully started
00:00:26.765 [N] Mle-----------: RLOC16 9800 -> fffe
00:00:27.265 [N] Mle-----------: Attach attempt 1, AnyPartition reattaching with Active Dataset
00:00:33.765 [N] RouterTable---: Allocate router id 38
00:00:33.765 [N] Mle-----------: RLOC16 fffe -> 9800
00:00:33.768 [N] Mle-----------: Role detached -> leader
00:00:33.770 [N] Mle-----------: Partition ID 0x5df7c8e8
[NOTE]-BBA-----: BackboneAgent: Backbone Router becomes Primary!
00:00:36.748 [W] DuaManager----: Failed to perform next registration: NotFound
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::24f2:1dff:fe79:d7f/veth9454c1a/17
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::24f2:1dff:fe79:d7f/veth9454c1a/17
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::24f2:1dff:fe79:d7f/veth9454c1a/17
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::24f2:1dff:fe79:d7f/veth9454c1a/17
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::685d:2cff:fe10:8a96/veth393885d/16
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::24f2:1dff:fe79:d7f/veth9454c1a/17
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::24f2:1dff:fe79:d7f/veth9454c1a/17
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::4c3d:6aff:fec7:fa24/veth2e9c6e2/18
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::4c3d:6aff:fec7:fa24/veth2e9c6e2/18
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::4c3d:6aff:fec7:fa24/veth2e9c6e2/18
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::4c3d:6aff:fec7:fa24/veth2e9c6e2/18
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::4c3d:6aff:fec7:fa24/veth2e9c6e2/18
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface fe80::fcbf:45ff:fe65:e82e/vethc45008c/19
00:02:31.981 [W] P-InfraNetif--: failed to send ICMPv6 message: Cannot assign requested address
00:02:31.981 [W] RoutingManager: Failed to send RA on infra netif 2: Failed
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
00:02:32.371 [W] P-InfraNetif--: failed to send ICMPv6 message: Cannot assign requested address
00:02:32.371 [C] RoutingManager: RsSender: Failed to send RS 1/3: Failed
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2
Default: mDNSPlatformSendUDP got error 99 (Cannot assign requested address) sending packet to ff02::fb on interface 192.168.0.5/enp1s0/2

Any idea on what could be the problem or anything I could try?

Thanks!

WallyR · June 23, 2025, 12:08am

You need to have IPv6 enabled and not run HA multihomed.
You can run Matter with VLANs, but HA, the Matter server, OTBR, phone for commision and devices needs to be in the same network, unless you really learn IPv6.
Your IPv4 knowledge is pretty useless when it come to IPv6.

retel · June 23, 2025, 5:26am

Thanks WallyR!

When you say multi homed, do you mean not to run skyconnect with multiprotocol? No that shouldn’t be in use if I understood correctly that needs to be enabled manually somehow.

Ipv6, I see it is enabled in HA but not in my router? Is that the problem? Even if I want to add a Thread product? I thought Thread was it’s own separate network. I will add this a bit later today. Thanks!

WallyR · June 23, 2025, 7:30am

Multihomed means running it with multiple network interfaces connected.

retel · June 23, 2025, 8:02pm

Thanks for the input and clarifications WallyR!

I don’t have multihomed network setup. I have been planning it but it’s still in the backlog. All devices on the same network and SSID.

I checked the network settings in HA and there IPv6 is already enabled:

IPv6 however wasn’t enabled in my Unifi Router so I added it there by the help of this thread but by the comment I also learned that maybe it wouldn’t be needed since it is only needed for HA. But I added it either way:

But it still doesn’t work and I have the same error in the logs. If I understand this correctly my HA and router now has two different IPv6 setups? Do I need to make my HA use this setup from the router? Should I add the router as the DNS server, and what address is that then, is it the Gateway IP shown in the screenshot or is it the Link Local IP? Haven’t used IPv6. For my HA IPv4 setup my router is the gateway and DNS server.

Thanks!

WallyR · June 23, 2025, 9:31pm

What firmware do you have on your SkyConnect?

Multi-PAN firmwares are really not recommended anymore and the development of that have been put on pause.
If you have Multi-PAN firmware, then I suggest you flash it with Thread-only firmware instead.

retel · June 23, 2025, 9:44pm

Thanks! Yes, I’m also looking to use this dedicated for Thread as I have another device, sonoff, to handle Zigbee. From what I understood the OTBR addon will flash the dedicated and latest firmware during start up? That is also what I can read from the log that I pasted. If I’m reading this correctly it should be using FW 2.4.4.0?

retel · June 25, 2025, 7:45pm

Hey WallyR, did you have any other recommendations or ideas what the error message could mean or how to solve it? Thanks!

retel · June 26, 2025, 6:53am

If anybody finds this thread. I got a new device and this one properly commissioned. I still have the error as mentioned in the logs above but it doesn’t appear to actually cause any problems.

WallyR · June 26, 2025, 7:08am

I have searched a lot, but I have not found any solution.
It seems that your OTBR can not send IPv6 information to your other addons, so try to restart the HA host.

retel · June 26, 2025, 7:14am

Ok, then I understand the error message thanks. I can mention that I have now successfully connected my router so it gets a IPv6 address from the ISP and this is then propagated to my internal network and also HA has stopped using it’s internal one. I have rebooted the entire HA host after this. Still have the same messages but again, this doesn’t appear to have any effect on my being able to commission a device.

[NOTE]-BBA-----: BackboneAgent: Backbone Router becomes Primary!
00:00:36.147 [W] DuaManager----: Failed to perform next registration: NotFound
00:00:50.525 [W] P-RadioSpinel-: Error processing result: NoAddress

WallyR · June 26, 2025, 8:23am

It seems most of those errors are related to addons that do not run IPv6 or mDNS.

retel · June 26, 2025, 8:38am

You mean other addons are causing this errors? I have 15 addons installed, but I thought all of them communicated with IPv4? Shouldn’t they just use the network settings from HA?

WallyR · June 26, 2025, 9:07am

They use the network settings in Docker.
The network settings in HA seems to only affect HA itself.
Docker have IPv6 enabled, so the addons will have it too, but not all of them seem to use it or have all the services for it enabled.

retel · June 26, 2025, 9:21am

Okay, so if host docker has a separate IPv6 enabled it should still use the IPv6 config that I have setup in my router now right. So, yes, as you say then, some addons aren’t using it correctly. I don’t know why the OTBR addon shows errors about that though. Thanks for all the help!

WallyR · June 26, 2025, 9:30am

No idea either.
It looks like some of the lines are not even log lines, since they are without timestamp and indication of log level.
But if it works, then just ignore it and let the devs deal with that.

wmaker · June 26, 2025, 7:17pm

retel:

[NOTE]-BBA-----: BackboneAgent: Backbone Router becomes Primary!
00:00:36.147 [W] DuaManager----: Failed to perform next registration: NotFound
00:00:50.525 [W] P-RadioSpinel-: Error processing result: NoAddress

The “DuaManager” as far as I know has to do with a Thread feature that can use multiple Thread networks in a common “Domain”, and this feature is more for commercial deployments and not for HA, so this is an error you can ignore.
The RadioSpinel error however is more concerning. But it may be a one-time event as I don’t see it in your first logs.

retel · June 26, 2025, 7:32pm

Hi Tommy, thanks for the input!

Good to know that the “DuaManager” can be ignored.
The “RadioSpinel” error is recurring and is printed repeatedly throughout the log. Any idea what it means?

03:26:58.780 [W] P-RadioSpinel-: Error processing result: NoBufs
03:26:58.780 [W] P-RadioSpinel-: Error waiting response: NoBufs
03:31:58.724 [N] MeshForwarder-: Failed to send IPv6 UDP msg, len:133, chksum:e065, ecn:no, to:4ad86858165156cf, sec:no, error:NoAck, prio:net, radio:15.4
03:31:58.724 [N] MeshForwarder-:     src:[fe80:0:0:0:34ff:31e3:185d:a5c3]:19788
03:31:58.725 [N] MeshForwarder-:     dst:[fe80:0:0:0:48d8:6858:1651:56cf]:19788
03:32:23.546 [W] P-RadioSpinel-: Error processing result: NoBufs
03:32:23.546 [W] P-RadioSpinel-: Error waiting response: NoBufs
03:33:09.966 [W] P-RadioSpinel-: Error processing result: NoBufs
03:33:09.966 [W] P-RadioSpinel-: Error waiting response: NoBufs
03:34:07.643 [W] P-RadioSpinel-: Error processing result: NoBufs
03:34:07.643 [W] P-RadioSpinel-: Error waiting response: NoBufs
03:35:48.810 [W] P-RadioSpinel-: Error processing result: NoBufs
03:35:48.810 [W] P-RadioSpinel-: Error waiting response: NoBufs
03:35:48.810 [W] P-RadioSpinel-: Error processing result: NoBufs
03:35:48.810 [W] P-RadioSpinel-: Error waiting response: NoBufs

wmaker · June 26, 2025, 7:38pm

NoBufs generally means something has used all the buffers that it allocated, and kinda guessing this is on the OTBR side of the Spinel and not the radio side. Its not a good thing, but I don’t recall seeing this kind of error before from other community forum users.

I can only suggest you completely powerdown the system, replug the ZBT-1 and then restart your system to see if this goes away.

HansZenth · July 11, 2025, 9:45am

Hi Peter,
For what it is worth - I do not know if it applies to your setup - but I was facing the exact same error messages in OTBR log, when trying to commission devices.
I was about to start deep-diving into IPv6, as I can see you have been doing - but was surfing a bit around and (among other stuff) watching a HA setup video for my radio device = a SLZB-06, which has been working flawlessly for the past 6 months…
My attention was caught by them mentioning that you need to sync your Thread credentials to the Android companion app twice, in order to have them fully synced - and to my surprise, that was the trick that made my day.
In the companion app, you need to go to Settings → Companion app → Troubleshooting → Sync Thread credentials. Doing this twice, resolved that error for me
/Hans