Upgrade to DSM 7.2 / Container Manager caused permission issues with Cache crashing Plex

[Tigeralum]

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My install of Plex has been rock solid on my Synology running in Docker for a long time. I made the mistake of upgrading to DSM 7.2 without researching the impact. Docker is now gone and my Plex (and Tautulli, FWIW) containers are now in Container Manager. OK, in and of itself this shouldn’t be a huge deal. However, since the upgrade, neither Plex nor Tautulli will work. When I look at the Terminal, I keep seeing the same error message:

libc++abi: terminating with uncaught exception of type boost::filesystem::filesystem_error: boost::filesystem::create_directories: Permission denied [system:13]:

“/config/Library/Application Support/Plex Media Server/Cache”, “/config/Library/Application Support/Plex Media Server/Cache”

I reset the system user permissions to read/write in that folder tree, but the same error keeps happening.

Is there a way to fix this?

Interesting, perhaps related, issue. When I was trying to edit the container it tells me that my path has an incorrect value. These are the same paths I’ve been using in Docker without issue since it was created.

[Tigeralum]

Some progress on this - I discovered that Docker didn’t mind uppercase letters, spaces, or dashes in file paths. Container Manager is OK with that on the Synology path side, but it must be matched to all lowercase, no spaces, no dashes.

For example, I have a folder called TV - Ended. In Docker this looked like
/volume1/TV – Ended:/media/TV - Ended
in Container Manager this must be:
/volume1/TV – Ended:/media/tv_ended

Now, that didn’t resolve my Cache permission error, but it does show one HUGE difference in how the files are handled between the two different applications.