TMDB not working with IPv6

[olevelo]

TMDB stopped working all of a sudden, either when adding new media, or going to Identify manually.  I get a timeout in the logs.  Found several threads about this and all of the solutions involved disabling IPv6.  I tried this, and it did indeed work.  However it's not a long-term solution for me, because my ISP uses CGNAT and so I only have IPv6 for in-bound connections.  I could potentially disable IPv6 on just the Jellyfin docker container, but I'm not sure what issues that would cause.  But I don't see why I should need to when it worked fine until today (literally was fine yesterday).  Surely there's some other solution?

Edit:  Did a little more investigation.  I can't ping the IPv6 address that api.tmdb.org is resolving to.  However, on a remote server I have, I can, and I noticed it has a different address it's resolving.  That address I can ping!  First time I've seen that.  So it seems to not be a Jellyfin specific problem...but also not sure how to fix it.  Again, it wasn't an issue yesterday or ever before (not sure if the IPv6 address changed recently, but using Google DNS).

[TheDreadPirate]

I can't ping the IPv6 address that api.tmdb.org is resolving to.

I'm assuming you did this on the host that is running the Jellyfin container.

Is the host configured to support IPv6?  Same with the router?  I have IPv6 setup throughout my home and most of my connections are IPv6 for Jellyfin.  Including for TMDB.  So definitely not a Jellyfin thing.

[olevelo]

I can't ping the IPv6 address that api.tmdb.org is resolving to.

I'm assuming you did this on the host that is running the Jellyfin container.

Is the host configured to support IPv6?  Same with the router?  I have IPv6 setup throughout my home and most of my connections are IPv6 for Jellyfin.  Including for TMDB.  So definitely not a Jellyfin thing.

Yes to all.  Again, everything has been working fine for over a year.  Nothing has changed in my configuration.  Literally the only difference from the day before was copying a new movie to the server.  As I said, I've had to have IPv6 setup on all of this because my ISP uses CGNAT.  But now the only way to get Jellyfin to scan media is to disable IPv6.