IP autodiscovery function fails when the Emby server runs in a docker container

[m4tt075]

Observation: Local authentification procedure keeps failing, despite of correct user credentials

Expectation: Local authentification succeeds

Relevant log entries: 2021-03-20 16:28:46.360 T:12024 ERROR <general>: [mediaimporter.emby] error retrieving response from POST http://172.20.0.4:8096/emby/Users/AuthenticateByName: HTTPConnectionPool(host='172.20.0.4', port=8096): Max retries exceeded with url: /emby/Users/AuthenticateByName (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x000002BD13B28D30>, 'Connection to 172.20.0.4 timed out. (connect timeout=2)'))

Context:

• The Emby server runs in a docker container in bridge mode
• 172.20.0.4 corresponds to the IP of the Emby container within the bridge network
• The Emby server contains a setting to override the actual IP address of the Emby server, which is correctly set to the server IP address running docker and the Emby container within my LAN

Potential fixes (TBC):

• [Preferred] The IP autodiscovery function fetches the override IP value from the Emby server and utilizes it if it's non-empty
• Addition of a mediaimporter.emby setting to override the automatically discovered IP address of the Emby server itself

[Montellese]

Thanks for the report. Do you know if the IP address you manually configured ends up in the discovery message broadcasted by the Emby server? Because the add-on simply gets the IP address from there. If that one isn't correct I'm not sure how the override IP could be retrieved from the Emby server since the add-on can't know how to access it. In that case a setting to manually change the URL would be the only way....

[m4tt075]

Thanks for your quick response.

I'm not sure about where I can find the discovery message you mention. I've activated debug logging in kodi, but could neither find the actual server IP nor the hostname within it. If I need to look elsewhere, please do let me know...

What I do know though, is that this IP address should(TM) be announced somehow, at least if I believe the help text of the corresponding setting within the Emby server. It reads:

Optional. Überschreibt die lokale IP-Adresse, die der Server Emby-Apps zeigt. 
Wenn leer, wird der Server die lokale Netzwerkadresse ermitteln.

I'd freely translate that as:

Optional. Overrides the local IP address, which the server exposes to Emby-apps. 
When empty, the server will evaluate the local network address.

EDIT: I found some jellyfin documentation indicating that the discovery message is sent on UDP port 7359. I used wireshark to look into it. Apparently Emby uses that port for the discovery message, too. It seems to send an IP address, the client ID and the client name. It seems to contain the (wrong) bridge network IP though. So either the override IP is sent elsewhere, or there is a bug in the emby server. I'll start inquiring with them, too. If I learn anything new, I'll let you know...

[Montellese]

Thanks for the investigation and no need to translate German since I live in Switzerland ;-)

Yeah the discovery message contains the server's ID, name and IP address which is used by mediaimporter.emby to prepare the discovered media provider.

[m4tt075]

No news from the Emby forum. I've found a workaround but still encountered unexpected behaviour. Here is why:

• Doing more research I've found older forum threads with people indicating similar problems. The general recommendation was not to run the Emby docker container on the bridge network, but on the host network.
• Easily enough, I've changed the Emby container configuration accordingly
• Trying to connect, I still could not authenticate though. The log file indicated that the media importer add-on still tried to request information from the old, wrong bridge network IP address
• I started wondering whether this is a caching issue. I uninstalled the Emby media importer add-on, ensuring the addon-data folder was empty and reinstalled it again
• Nothing changed. To overcome the problem I simply wiped the whole userdata folder and started from scratch
• This time the installation of the add-on and authentication worked instantly, without any problems

I actually still believe that the Emby server keeps broadcasting the wrong IP address and not what is defined via override. But could it also be that the server IP address is just evaluated once, on initial configuration? And if so, would it be better to update it whenever the access settings are entered in order to account for changed configurations?

[Montellese]

Thanks for the details. You are right, the mediaimporter.emby add-on currently doesn't support updating the URL / IP address of a discovered provider. It does detect changes to the name but not to the URL because that one is stored in the custom settings of the media provider. In that case manually deleting the media provider, restarting Kodi and waiting for the media provider to be properly detected would have solved the problem as well. But I agree that this is not very intuitive.

I'll have to look into this. Off the top of my head I can't think of a simple solution due to how the URL is stored.

Either way I think having the possibility to manually change the URL of a detected Emby server is a good idea. As mentioned by LongMan I've already done this for mediaimporter.plex so it shouldn't be too hard to add here as well.

[m4tt075]

Thanks for the follow-up and your explanations. All makes sense.

And from additional reading on problems with network setups and autodiscovery on the Emby forum over the weekend, I also agree with your conclusion.

Many thanks for your great work and all your support on this!

[Montellese]

Can you give the improvement/change_url branch a try? It adds a button to the media provider settings which allows you to change the address / URL of the Emby server.

[m4tt075]

Many thanks, @Montellese. I've tested your changes and can confirm that it's working.

Here my test in detail:

• I've downloaded the zipped add-on from the branch you've referenced and installed it in Kodi
• I've reverted all changes to the Emby server container again, i.e. I've changed it back to bridge mode, added the UDP ports again and restarted the container
• I've started Kodi. The media importer add-on could still authenticate, but that wasn't surprising as it was still configured to the old (correct) server host IP address
• Following your advice to reset the configuration, I've deleted the Emby media importer and restarted Kodi
• Upon restart, Kodi announced that a "new" Emby server has been found
• Entering into the configuration, the authentication failed (as expected)
• I've changed the IP address to the correct one manually using your new setting.
• Afterwards, authentification and synchronization succeeded without problems.

I still don't know why the Emby server is not broadcasting the override IP, but that is a bug or at least non-intuitive (to me) on their end.

Again, my sincere thanks for your work and contributions. I'm closing the issue as you've definitely fixed it. Thanks again.

[Montellese]

Thanks for the detailed feedback. I've pushed the commit to the master branch so it will be part of the next release.

[m4tt075]

Just to close the loop: The Emby team have acknowledged the problem / inconsistency and promised that they will fix it with the next release. Then, the broadcast message should actually entail the IP address in the Emby server override. So, eventually, it seems we'll even have two solutions to the problem... :-)

Here the link for reference: https://emby.media/community/index.php?/topic/96249-emby-server-discovery-broadcast-ignores-network-override-setting/