UPnP based discovery does not work on host networked docker container

  • Platform information:
    • Hardware: ARMv7 rev 3 (v7l) / 2 GB
    • OS: Raspbian Buster (Linux/5.10.103-v7l+ (arm))
    • Java Runtime Environment: Eclipse Adoptium 11.0.17 (Temurin-11.0.17+8)
    • openHAB version: 3.4.1 (from this docker image)
  • Issue of the topic:

SSDP based discovery does not seem to be working, as it does not find most of the devices on my network.

Currently I have 3 devices on my network which I expect to be able to discover:

  • A Canon printer
  • 2 LG webOS TVs

These and all of the computers mentioned in the post are connected to the same local network, which is addressed as

The problem only occurs on my Raspberry Pi device, where I intend to run openHAB, which is normally run as a docker-compose stack, in which the openhab container is only given the host network.
For the Canon printer I have installed the IPP binding. This device has ben discovered automatically.
For the webOS TVs I have installed the LG webOS binding. These devices are not discovered automatically, neither manually by clicking on the Discover button on the “Add a new Thing: lgwebos” page, despite them being turned on (not just standby, they emit light and sound) and configured for control from their android app.

If I run the same version of openHAB on my windows PC (downloaded from here), it has already discovered the printer and the TVs when I get to open the Things page of my instance: the devices are waiting for me in the Inbox.

If I run the same version of openHAB in an ubuntu virtual machine on my windows pc, with Docker by the docker run --name openhab --net=host openhab/openhab:3.4.1 command, that has also discovered all of these devices by the time I get to the Things page, and they are visible in the Inbox.

If I forget about docker compose and instead run openhab with the docker run --name openhab --net=host openhab/openhab:3.4.1 command on this problematic raspberry pi, the problem persists: the TVs are not found, even though I have installed the lgwebos binding. Manually starting a discovery for this binding does not find the TVs either.

  • If logs where generated please post these here using code fences:

By default, no relevant logs appear.
Increasing the logging level of the “org.openhab.binding.lgwebos” and " com.connectsdk" loggers does not log anything either while manually running a discovery.
If I also increase the logging level for “org.jupnp”, I see that openHAB receives discovery responses from the TVs.

I have attached logs and the log level configuration. I’ll try that again when I get home. I was unable to pipe the output of log:tail to a file, log:display only shows a handful of lines however I parameterize it, and they dont’t respect --no-color.
Note that the loggers com.connectsdk, org.openhab.binding.lgwebos and org.jupnp are set to TRACE level logging.
I did a log clear before saving the output. If startup events would also be useful please let me know and I’ll upload a log starting from a restart.
You may see the following notable IP addresses in the log:

  • - my physical home network, to which computers, the printer and the TVs are connected
  • - the raspberry pi which runs openhab
  • - one of the LG TVs

It took more time for me to be able to get back to this, but I have uploaded the logs here.
I wasn’t able to upload it here, as with its 2,2 MB size it is above the size limit.
I have seen that a new update was released, so the logs were made with openHAB version 3.4.2, still in a Docker container, created and started with the same settings as before.

The logs start from starting up openHAB.
It includes when I have manually started discovery for the lgwebos binding (with the “Scan” button on the “Add a new Thing” page), and it ends when the discovery process has seemingly ended (~30 seconds after starting discovery, when the log output has became more quiet).
The log levels were set up this way:

openhab> log:get
Logger                                             │ Level
ROOT                                               │ WARN
com.connectsdk                                     │ TRACE
javax.jmdns                                        │ INFO
javax.mail                                         │ ERROR
openhab.event                                      │ INFO
openhab.event.AddonEvent                           │ ERROR
openhab.event.ChannelDescriptionChangedEvent       │ ERROR
openhab.event.InboxUpdatedEvent                    │ INFO
openhab.event.ItemAddedEvent                       │ ERROR
openhab.event.ItemChannelLinkAddedEvent            │ ERROR
openhab.event.ItemChannelLinkRemovedEvent          │ ERROR
openhab.event.ItemRemovedEvent                     │ ERROR
openhab.event.ItemStateEvent                       │ INFO
openhab.event.RuleAddedEvent                       │ ERROR
openhab.event.RuleRemovedEvent                     │ ERROR
openhab.event.RuleStatusInfoEvent                  │ ERROR
openhab.event.StartlevelEvent                      │ ERROR
openhab.event.ThingAddedEvent                      │ ERROR
openhab.event.ThingRemovedEvent                    │ ERROR
openhab.event.ThingStatusInfoEvent                 │ ERROR
openhab.event.ThingUpdatedEvent                    │ ERROR
org.apache.cxf.jaxrs.sse.SseEventSinkImpl          │ ERROR
org.apache.cxf.phase.PhaseInterceptorChain         │ ERROR
org.apache.karaf.jaas.modules.audit                │ INFO
org.apache.karaf.kar.internal.KarServiceImpl       │ ERROR
org.apache.karaf.shell.ssh.SshUtils                │ ERROR
org.apache.karaf.shell.support                     │ OFF
org.apache.sshd                                    │ ERROR
org.eclipse.lsp4j                                  │ OFF
org.jupnp                                          │ TRACE
org.openhab                                        │ INFO
org.openhab.binding.lgwebos                        │ TRACE
org.ops4j.pax.url.mvn.internal.AetherBasedResolver │ ERROR
org.ops4j.pax.web.pax-web-runtime                  │ OFF
su.litvak.chromecast.api.v2.Channel                │ ERROR

Notable log events

I have taken a look at the files, and I have noted the following events in it:

Manual start of discovery:

2023-02-14 15:35:37.358 [TRACE] [.jupnp.controlpoint.ControlPointImpl] - Sending asynchronous search for: ssdp:all

The first time the discovery request was sent to the main local network:

2023-02-14 15:35:38.118 [DEBUG] [.jupnp.transport.impl.DatagramIOImpl] - Sending message from address: /

The first time a response to the discovery was received from the main local network:

2023-02-14 15:35:38.216 [DEBUG] [upnp.transport.spi.MulticastReceiver] - UDP datagram received from: on local interface: eth0 and address:

I suspect that this response is from openHAB itself, but a different component of it.

The second time a response to the discovery was received from the main local network:

2023-02-14 15:35:38.831 [DEBUG] [.jupnp.transport.impl.DatagramIOImpl] - UDP datagram received from: on: /

This is one of the webOS TVs. A little further it can be seen as it introduces itself as one.

The previous message was logged once again. Probably not that notable, but I found it interesting.

2023-02-14 15:35:38.933 [DEBUG] [.jupnp.transport.impl.DatagramIOImpl] - UDP datagram received from: on: /

The first time detailed information on the TV was requested from it.
The ... means that these logs events were close to each other in the log, but I have not copied in there others that seemed to be irrelevant.

2023-02-14 15:35:39.483 [DEBUG] [p.protocol.RetrieveRemoteDescriptors] - Sending device descriptor retrieval message: (StreamRequestMessage) GET
2023-02-14 15:35:39.537 [DEBUG] [org.jupnp.transport.Router          ] - Sending via TCP unicast stream: (StreamRequestMessage) GET
2023-02-14 15:35:39.547 [TRACE] [org.jupnp.transport.spi.StreamClient] - Preparing HTTP request: (StreamRequestMessage) GET
2023-02-14 15:35:39.555 [TRACE] [org.jupnp.transport.spi.StreamClient] - Creating HTTP request. URI: '' method: 'GET'
2023-02-14 15:35:39.605 [TRACE] [org.jupnp.transport.spi.StreamClient] - Waiting 10 seconds for HTTP request to complete: (StreamRequestMessage) GET

First response of the TV to the previous request:

2023-02-14 15:35:39.675 [TRACE] [otocol.async.ReceivingSearchResponse] - Received device search response: (RemoteDeviceIdentity) UDN: uuid:c5457ee3-5af0-6446-7af6-ff1d34c9b818, Descriptor:

Here is the first time this request would be sent again, but it sees that it had already have sent such a request to which it haven’t yet processed a response, so now it doesn’t send it again:

2023-02-14 15:35:39.698 [TRACE] [otocol.async.ReceivingSearchResponse] - Skip submitting task, active retrieval for URL already in progress:

While processing the request for the detailed information, it cannot process the SERVER header because of the formatting of the UPNP specification number:

2023-02-14 15:35:39.849 [TRACE] [upnp.model.message.header.UpnpHeader] - Invalid header value for tested type: ServerHeader - Missing 'UPnP/1.' in server information: Linux/i686 UPnP/1,0 DLNADOC/1.50 LGE WebOS TV/Version 0.9
2023-02-14 15:35:39.873 [TRACE] [org.jupnp.model.message.UpnpHeaders ] - Ignoring known but irrelevant header (value violates the UDA specification?) 'SERVER': Linux/i686 UPnP/1,0 DLNADOC/1.50 LGE WebOS TV/Version 0.9

While making a GET request to from my PC, I see that the SERVER header actually contains UPnP/1,0. However, when I was running openHAB on my PC, it was able to discover the TV.

The first time a different kind of response has arrived, which contains information about a UPnP service. Here the UPnP version number seems to be formatted as openHAB expects it:

2023-02-14 15:35:40.955 [TRACE] [upnp.transport.spi.DatagramProcessor] - HTTP/1.1 200 OK
Cache-Control: max-age=1800
Server: WebOS/4.0.0 UPnP/1.0
USN: uuid:6ff027f3-83c6-4fe7-a16c-089fdfef6302::upnp:rootdevice
ST: upnp:rootdevice
Date: Tue, 14 Feb 2023 14:35:39 GMT

This response has other variants too, each of which contain a different service in the USN and ST headers. One more example is this:

2023-02-14 15:35:41.344 [TRACE] [upnp.transport.spi.DatagramProcessor] - HTTP/1.1 200 OK
Cache-Control: max-age=1800
Server: WebOS/4.0.0 UPnP/1.0
USN: uuid:6ff027f3-83c6-4fe7-a16c-089fdfef6302::urn:lge:device:tv:1
ST: urn:lge:device:tv:1
Date: Tue, 14 Feb 2023 14:35:39 GMT

For some of these responses the logs complain that it was unable to parse the ST and the USN headers.

After these, to me it seems everything just gets repeated over 30 seconds, until openHAB gives up, but I may have missed some important logged events.

I was experimenting and I think I may have found what causes this.

The workaround

I’ve noticed that if I shut down any one of my other container stacks (with docker-compose down, which deletes the container and the docker networks that were made explicitly for the stack), and then I restart openHAB, openHAB will become able to discover devices on the network, including the LG TVs and the minidlna mediaserver (which is running on this same machine, in a different container).

What is causing this exactly

After some more experimenting it seems neither creating a certain amount of networks or containers in itself lead to openHAB not being able to discover devices, the actual thing that leads to this is when a certain amount of networks are being used by at least one container.

For example, if you already run openHAB on the host docker network, and then create 2 custom docker networks with the command docker network create [name], you will have 3 networks, which all are visible to the host OS, and also to openHAB.
Only one of them is used so far (the host one), the others will have the DOWN status, and they will not be visible in the “Settings > Network Settings > Primary Address” list, only in “Broadcast Address” in the same menu.
If you start a container (with docker run --network <network name> --detach containous/whoami, but you can use a different image, I choose this one because it keeps running and is relatively lightweight), and connect each of these new custom networks to this container (docker network connect <network name> <container name>, you can skip the one which you have given in the run command) those networks will be UP-ed, and they will also appear in the mentioned “Primary Address” list.
At this point, discovery is still working.
Now create and connect one more docker network to this whoami container.
Discovery is still working.
Now restart the openHAB container.
Discovery is now not working.
Now disconnect any one network from the whoami container, and restart openHAB.
Discovery is working again.

Conditions for the problem to appear

So far I don’t know if this is an openHAB issue, or a Docker one.

What I know, though, is that the discovery of openHAB will work fine if its container was started before a certain amount of networks were UP-ed, even if new networks are UP-ed later while openHAB is running, even though openHAB will see these new networks in the mentioned “Primary Address” list. The problem only happens when openHAB is started while this amount of networks are already UP-ed.

Also, the amount of networks needed to break discovery can vary.
On my Raspberry Pi, where I was initially testing openHAB, discovery worked fine until I had only 6 networks UP-ed, and the 7th broke it.
But then I continued testing this on an Ubuntu virtual machine on my x86 PC (because it is faster and nothing critical runs there so I have a free hand in testing), and there 2 networks are OK, and the 3rd one breaks it, however looking at the mentioned “Primary Addresses” list, in this environment for every network interface I have 2 addresses that start with 169.254., so eventually the limit may still be between 6 and 7 interfaces, but the rest is filled with these weird ones here (for 2 interfaces I have 2+4 addresses, for 3 I have 3+6).

Finally, when discovery is not working, I see lines like this in the log:

openhab    | 2023-02-18T13:47:24.727287554Z 14:47:24.726 [INFO ] [org.jupnp.transport.spi.StreamClient] - Timeout of 10 seconds while waiting for HTTP request to complete, aborting: (StreamRequestMessage) GET

These do not appear when discovery is working.

One more thing I almost forgot.

When these timeout logs do appear, if I open a shell in the container (with docker exec -it openhab bash) and run curl for one of the not responding addresses, I’ll get a response that looks to be ok:

docker-compose logs -ft | grep --text "Timeout of 10 seconds"
openhab    | 2023-02-18T14:05:07.723277151Z 15:05:07.722 [INFO ] [org.jupnp.transport.spi.StreamClient] - Timeout of 10 seconds while waiting for HTTP request to complete, aborting: (StreamRequestMessage) GET
openhab    | 2023-02-18T14:05:08.096812184Z 15:05:08.095 [INFO ] [org.jupnp.transport.spi.StreamClient] - Timeout of 10 seconds while waiting for HTTP request to complete, aborting: (StreamRequestMessage) GET
docker exec -it openhab bash
root@rpi-docker-openhab:/openhab# curl
<?xml version="1.0" encoding="UTF-8"?>
<root xmlns="urn:schemas-upnp-org:device-1-0" xmlns:dlna="urn:schemas-dlna-org:device-1-0">
    <friendlyName>[LG] webOS TV SK8100PLA</friendlyName>
    <manufacturer>LG Electronics</manufacturer>