[URGENT] Large Server (90TB) — Library Scans Stalling on Synology NAS

[BaNanaBlocks 9]

Running into a persistent issue I haven’t seen in years and could really use an experienced set of eyes.

• Emby Server: Windows PC
• Storage: Multiple Synology NAS devices (currently 2, adding a 3rd)
• Library Size: ~90TB

Issue:
Two of my largest libraries will not complete a scan.

• Scans start but never finish
• Content remains unavailable for playback
• Metadata is not updating

This has been happening consistently for several days now.

Impact:
This is effectively blocking access to a large portion of my media and breaking normal server operation.

What I’ve tried:

• Re-running scans multiple times
• Waiting extended periods (no completion)

Request:
Looking for guidance on:

• Identifying what’s causing the scan to stall
• Logs or diagnostics I should pull immediately
• Known issues with large libraries + Synology setups

Happy to provide logs, screenshots, or run targeted tests right away.

Edited March 27 by BaNanaBlocks
Added additional information.

[js28194 42]

Never had a large library scan prevent any playback.  They can happen concurrently with no issues.  The better minds would need the EmberServer.txt log file to take a peek.  Sounds like drive/access issue.

[BaNanaBlocks 9]

1 hour ago, js28194 said:

Never had a large library scan prevent any playback.  They can happen concurrently with no issues.  The better minds would need the EmberServer.txt log file to take a peek.  Sounds like drive/access issue.

Thank you. I've been planning to migrate the TV Shows library to a new NAS. Once that's complete, I'll see if the problem persists. I'll keep this post updated.

[Nathanael 5]

Your symptoms look more like network bandwith then a problem with the server. My 60TB library does not have this issue, and i have an old low power 2011 xeon.

[BaNanaBlocks 9]

Now that all the data has finally transferred over to the new NAS, everything seems to be functioning as usual. You would think that with 2TB of free space on the NAS, EMBY wouldn't have any caching issues, but I can only guess that that was the issue since no one from EMBY ever responded to my issue. I guess this is not the way to contact someone from EMBY. Oh well. I'll close this issue and mark it as resolved. 

[BaNanaBlocks 9]

On 3/28/2026 at 1:55 PM, Nathanael said:

Your symptoms look more like network bandwith then a problem with the server. My 60TB library does not have this issue, and i have an old low power 2011 xeon.

I have all my NAS devices, the EMBY server computer, and our internet provider on a 1Gb network, so I don't think bandwidth should be an issue. But I will definitely look into that, just in case. Thank you for the response.