New to Emby: Unable to generate thumbnails or connect Emby account

[Herodotus 1]

I am in the process of switching from Plex to Emby. The first problem I have is that none of the thumbnails for my movies are being generated. I've already tried rescanning, refreshing, and enabling everything under Fetcher Settings. The library scan is stuck at 90% and nothing is happening for hours. The NAS is not showing any signs of high CPU or memory usage.

It doesn't help that Synology keeps showing Emby is if it's not running, even though I keep pressing "Run":

I thought maybe this is a cosmetic issue since I can still access the Emby server from the browser, but I don't see any Emby processes in my Resource Monitor in Synology NAS.

I also cannot link my account to Emby (created earlier today):

I've tried disabling VPN. I have also enabled all the port forwarding and firewall rules as I have for Plex. One thing to note is that I'm behind CG-NAT (the main reason why I'm leaving Plex). I don't know if that could be the reason why Emby isn't connecting, but I have already created an IPv6 firewall rule and directed Empy to use my IPv6 addrress under Network-->External domain-->https://[IPv6 address]:9000 (custom port).

Any insight would be appreciated.

 

EDIT: I also found out that I am unable to play pretty much any movie. So far, only one movie played (1080p). I've tried both in the browser and android app. And I'm using Emby 4.5.4.0

 

Edited January 7, 2021 by Herodotus
Additional details

[Luke 37093]

Hi there, can you please attach the emby server log?

Thanks.

[Herodotus 1]

Hi Luke, I sent you the log via DM rather than posting here since I'm not sure what the log contains.

[Tandhruil 21]

Hi,

I've a DS220j synology and the initialisation of the database was very long (more than a hour).

It's because of the memory size of the NAS (512 MB, it's a shame !).

I must say that since the 4.5.x version of emby, the server works far better than with the 4.4.3 release.

Bytheway, I've disabled the Synology indexation service which use too much ressources. If you don't need the Synology multimedia services it's no need.

What's the reference of your Synology ?

 

 

[Herodotus 1]

After running overnight, the scan has advanced by only 5%! As I mentioned, my system resources in the NAS look unused. I have the DS1618+ with 32GB memory. The movie folder isn't huge either - about 300 of them. Many of the thumbnails seem to be loaded now, but they're completely off - except maybe a couple of proper movie thumbnails, the rest look like distorted screenshots from the movie. I'm assuming it's because the metadata isn't detected correctly? The filenames match the naming convention of Emby and they are all detected just fine in Plex. It's the same folder.

 

[Luke 37093]

All of your outgoing connections are timing out and failing. That's probably a big reason for the slow initial scan. It looks like something is blocking Emby Server from sending out those requests. Typical causes are firewall, security software, or vpn. I would look into this. You could also try disabling ipv6 in your router and see if that helps. 

[Herodotus 1]

@Lukedisabling IPv6 is not an option. That's the entire reason why I'm going for Emby to begin with. I am behind CG-NAT.

Cayars has been trying to help me in DMs, but since other Synology users might be able to chime in, I wanted to share this here too. I am still having issues with Emby being blocked. When I open my firewall by disabling the rule that drops all connections without a specific passthrough, Emby seems to start working. Thus, something in the firewall is blocking Emby even though I have already opened all the ports I was told to open. Can someone please chime in and let me know if you're seeing any ports I'm missing below? 172.16.0.26 is the NAS where Emby is hosted. 2604:2800... is the same NAS's IPv6 address. I have set custom external ports of 9000/9001. I have already tested and I do have remote access to Emby via IPv6 from my cell network. Here are the firewall rules in Synology RT2600ac router:

And these are the forwarding rules:

 

Am I missing anything?

[Luke 37093]

Unfortunately as the problem is specific to the environment, there's no way for me to know why the outgoing requests are being blocked, I can only confirm that this is what appears to be happening. The reasons I listed are the most common causes.

[Herodotus 1]

Well, I think we can already rule out VPN, security software, or even IPv6 as the cause. Given the fact that Emby works as soon as I disable the very last rule in my firewall (Drop All), proves that this is a firewall issue. And as a firewall issue, it really seems to me like there is a port that is missing from the firewall rules. Unfortunately, Synology does not have a firewall log where I can look to see what is exactly being blocked.

[Luke 37093]

17 hours ago, Herodotus said:

Given the fact that Emby works as soon as I disable the very last rule in my firewall (Drop All), proves that this is a firewall issue.

That's great investigation. Thanks for the feedback !

[kaj 242]

21 hours ago, Herodotus said:

Well, I think we can already rule out VPN, security software, or even IPv6 as the cause. Given the fact that Emby works as soon as I disable the very last rule in my firewall (Drop All), proves that this is a firewall issue. And as a firewall issue, it really seems to me like there is a port that is missing from the firewall rules. Unfortunately, Synology does not have a firewall log where I can look to see what is exactly being blocked.

I'm not sure, but I think Synology follows the firewall rules in order, so your final rule could be blocking ones above. Try moving the Drop All to the top position.

[Herodotus 1]

Since it took me a while to troubleshoot things, I wanted to post the final solution for others. I'll be brief:

• Turned out that Emby was unable to connect to outside servers to get metadata information because it was relying solely on IPv6 outbound connections. Thus, the rule I was missing was the IPv6 address of the NAS where Emby was located--I had to allow all outbound IPv6 connections. This is interesting because all my other apps, Plex, and the Linux system itself did not have this issue and were using the IPv4 LAN addresses for outbound connections without issues. But Emby needs an explicit outbound IPv6 rule to work. I don't know if this is something that can be changed in the app itself, but could be useful to alert the program engineers.
• RE: issue where Synology NAS shows Emby app as not running. The solution is to go into Emby, shut it down, and then start the Emby app from within Synology. This resets it to the correct "Open" status
• I had continuous issues with movie posters/thumbnails not loading even after I had unblocked the connections. The only thing that ended up working was to remove the entire Library from Emby and add it again. Refresh metadata and Scan Library did not work, even though I tried multiple times. As soon as I recreated the library in Emby, the whole thing loaded in probably 30 seconds with almost everything identified correctly
• @kaj: Synology firewall rules are indeed sequential. The highest priority rules go at the beginning. The Drop All rule must go at the very end, otherwise it will block all the rules that come after it. Had my rules been really blocked, I wouldn't be able to access the internet.

 

Now I have to figure out how to make a secure remote connection to Emby using my Let's Encrypt certificate in Synology NAS. From what I've seen so far, it seems the easiest solution is a Reverse Proxy setting. Of course, it's only easy if it works out from the first try, which has not been the case so far with the other configurations...

Edited January 10, 2021 by Herodotus

[kaj 242]

I used this guide:

Emby Secure Your Server : Emby

Couldn't get reverse proxy to work well enough when dealing with remote users and transcoding. Probably just my stupidity...but at least the above guide worked, so everyone connects over SSL

[Herodotus 1]

Thanks for that link - my only reason for SSL is specifically for remote access. If you've had issues in that arena, that would make me weary.

The guide I intend to follow is this one and seems simpler on the surface, if you already have Synology NAS. In a nutshell, it seems to remove any particular setting or certificate requirements for Emby and allows Synology to take over everything. If @CChris is still around, I would wonder if his remote connections have been robust before I go down this path since this is his guide (thanks for that!):

By the way, although I wish some things were easier to achieve in Emby, as is the case with Plex, I must give kudos to the Emby team for having implemented a proper IPv6 support. More and more ISPs are abandoning IPv4 and switching to CG-NAT. Plex, in all of its glory, has failed to implement proper IPv6 support despite user requests starting back in 2013. I spent about 2-3 days trying to get Plex to work remotely on an IPv6 and even communicated with Plex community/team member and Synology support, but utterly failed (DNS rebinding protection, IPv4 to IPv6 forwarding, etc, etc). With Emby, a remote access worked immediately. Of course, then I had to spend quite a bit of time trying to make the local access work. However, my issues won't be applicable to most people only because I have strict firewall rules that drops all connections that are not specifically open. That's the reason I had these issues. Now I have a chance to check out how things work in Emby.

[CChris 58]

Hi, I'm still around... at least sometimes :)

I am not using an Installation on Synology anymore, but the setup is still pretty similar to that on Synology.
I have switched to a virtualized Server environment, where Emby is running on a debian based machine.

Another machine is running an nginx Webserver - working as a reverse proxy.
The nginx Server is listening to a Domain and this domain is sequred with an SSL Certificate.

So emby isn't using anything of the remote controll functions - instead, the nginx is managing all these things.
And yes, this is pretty stable :)