mysterious connection error during external access

[frylich 9]

Hello dear emby team & community,

One of the external users of my Emby server has a strange problem:
It is possible to establish a connection to the server via LTE with a cell phone without any problems, but as soon as a connection from the same cell phone is to be established via WLAN, a connection to the server is not possible anymore. The same thing happens with other devices (notebook or firetv) on the same network.

Now to my question:
Can one of you please give useful tips as to what this could be? I look forward to your ideas.

Thank you

[Happy2Play 9780]

What platform but almost sounds like firewall issue?

[frylich 9]

Hello Happy

the server: qnap nas

the user: android, or windows, or whatever, doesnt matter

everey other user has no issues

maybe firewall, but which one? the user firewall? he got none, maybe the router or is it possible that the isp is blocking emby?

thanks

Edited November 5, 2024 by frylich

[Luke 42079]

Quote

but as soon as a connection from the same cell phone is to be established via WLAN, a connection to the server is not possible anymore.

Hi, what exactly happens when you try?

[frylich 9]

Hello master chief of bazinga

Below are a few screenshots from the user and the server.

Would the server log be useful to you as a PM?

[Luke 42079]

Hi, are you sure the server was up and running and not asleep at the time you tried to connect?

What time did you try to connect?

Also are you able to update to Emby Server 4.8.10 ?

[frylich 9]

the server is never asleep, thats for sure not the issue. like i wrote in the first post, this happens when one of the external users try to connect from his wlan, at the same time he can connect via lte, same device, same account, same server. it happes to all accounts or devices inside this network of his wlan.

did you read my pm?

yes i update the server tomorrow.

Edited November 6, 2024 by frylich

[frylich 9]

in case this is not clear, the screenshots are taken at the same time, the server noteiced the access attempt by the user, but on the users side is seems there is no connection possible or even a server online displayed

[frylich 9]

Hello Luke,

the update didnt solve the issue and now the server dont even notices the user whos trying to login.

did the serverlog help?

I hope u have some powder left in your gun of ideas

greetings

[Luke 42079]

Quote

now the server dont even notices the user whos trying to login.

HI, what exactly do you mean by this?

Quote

did the serverlog help?

Since you've updated, can you please provide a new log example from the latest version? Thanks !

[frylich 9]

Morning Luke

with the old server version, the server detected the user's login attempt (see screen here in the post), and the server was displayed to the user as offline, with the new version this no longer works either.

the new log is send to you as PM.

Edited November 8, 2024 by frylich

[Luke 42079]

Quote

with the new version this no longer works either.

HI, can you please describe this in more detail? What exactly happens?

[frylich 9]

Hi Luke, I really have no idea how I could describe the situation in more detail. you know what the user does and what happens there, you know how the server reacts and two server logs. What information are you missing? I would be happy to help with my limited knowledge.

[pwhodges 2012]

On 05/11/2024 at 19:28, frylich said:

It is possible to establish a connection to the server via LTE with a cell phone without any problems, but as soon as a connection from the same cell phone is to be established via WLAN, a connection to the server is not possible anymore.

On 05/11/2024 at 20:12, frylich said:

everey other user has no issues

 

If it's user dependent, but Emby can't connect to log the user in anyway, that suggests something device dependent.

The first thing that comes to mind is the iPhone setting (I presume Android phones have a similar one) which is present for each app, enabling or disabling connection to wifi on an App by App basis.

Paul

[yocker 1249]

VPN problem?

[frylich 9]

12 hours ago, pwhodges said:

If it's user dependent, but Emby can't connect to log the user in anyway, that suggests something device dependent.

The first thing that comes to mind is the iPhone setting (I presume Android phones have a similar one) which is present for each app, enabling or disabling connection to wifi on an App by App basis.

Paul

Hi Paul, no because every other device will act the same inside the users wifi. The fritzbox of the user is on default settings, nothing special there. Every other streaming app is fine.

Edited November 9, 2024 by frylich

[frylich 9]

Problem solved

The reason for the error is that the host (NAS) and the external user (client) are at the same ISP and are not further away from each other. Carlo (Emby team) explained it like this: "It depends on the configuration of the ISP, it's subnets, levels of routers and use of CGNAT. This is often a problem in ISP setups where a pool of addresses from group A will never be able to communicate with a group B."

Now we change "never"

A possible solution that worked for me is the following:

- purchase a own domain name (no subdomain)
- change the domain nameserver to Cloudflare 
- set the domain up in Cloudflare free plan
- built a tunnel between the host (NAS) and Cloudflare
(via Cloudflare Zero Trust Dashboard and NAS Docker Container)
- change the default emby ports to supported ports by Cloudflare

=> Cloudflare is something like a detour in that case

Sources & Guides:
QNAP >> https://savoir-faire.neocities.org/tutorials/cloudflare_tunnel_on_qnap
Synology >> https://www.crosstalksolutions.com/cloudflare-tunnel-easy-setup/
Cloudflare Ports >> https://developers.cloudflare.com/fundamentals/reference/network-ports/

Edited November 12, 2024 by frylich