At first I thought this was a bug in libdvdcss as it really only affected pressed movies, but lately I've been having some strange issues mounting DVDs I just burned.

First, I want to rule out some hardware issues. This started happening on an old questionable DVD drive. I had another bay, so I added another DVD drive from an external enclosure...which had the same issue. Just to rule it out, I bought a brand new Samsung Super Writemaster drive from Amazon. And the problem still persists.

But today I went to burn a DVD (in the brand new drive), but after I reinserted the disk, it didn't automatically mount. So I went to the Disk Utility and saw a sight all too familiar:
http://s2.postimg.org/kcav0mv95/disks_84gbunknown.png

I have a theory that because I have 2 DVD drives, that it is trying to mount /dev/cdrom instead of, in this case, /dev/sr0. The thing is, though, that
will successfully mount the disk. That's what it should be doing automatically.

Here is what GNOME Disks reports after I mount the drive manually:
http://s28.postimg.org/4bb4ha3u5/odd.png

Would really like to know what's going on so I can file a bug report on Launchpad.

Thanks in advance.

Oh, I re-read it

No, neither drive is bad after I replaced the one I thought was bad. (And really wasn't). Both drives have the same issue.

This is a workstation PC (HP X series specifically). Ran a memory test last night and it came clean. I'm highly doubtful that it's anything hardware related, as things like a SATA controller or power supply would cause all kinds of problems. The only thing I might be skeptical of are the cables, but I don't think so for 2 reasons:
* I swapped them around, and the drives are still having issues.
* Both cables having the same exact issue would be highly unlikely.

What leads me to think this is a software issue is what I said in my first post, that I can mount it manually just fine. So I think it's something wrong with how it automounts the disk, I'm just not sure what the issue is.

It looks like the automounting software doesn't identify the udf filing system. One trick you could try would be to use the second drive exclusively for disks with that system, and to make an entry for /dev/sr1 in /etc/fstab, which the automounter should use.

if you search LQ forums for dvd and udf, there was a similar thread very recently.
iirc, the solution was that some linuxes don't support recent versions of udf.

You mean this thread? I already read that. That had to do with multiple users being logged on, and one user couldn't access the drive another user had mounted. I do have 2 users on my system (one for personal stuff, one for tutorial screencasts), but I almost never log in on both at the same time.

What I'm talking about is for some unknown reason, some UDF DVDs will not mount (but others will).

For example, I was watching Duck Dynasty S5, and Disk 1 read just fine, but Disk 2 didn't. Same UDF filesystem, same CSS encryption...I don't know what's going on.

january is not "very recent" in my book.

i meant this thread and i see now that it was about blurays, so not strictly dvd. it might or might not contain information relevant to your problem.

No I never have that problem. On a manual mount it works fine, no issues...even though it claims it has no clue what the filesystem is. Something else I find odd is that I can completely omit the -t in the mount command, and it still works given it doesn't know what the filesystem is.

Obviously there's nothing wrong with mount, that's working just fine. I think it has something to do with GNOME. I'll try mounting some problematic DVDs from a Kubuntu live USB.

Arg! This is driving me nuts! This is happening now on both my desktop AND laptop! Read this and found that it has to do with how the kernel has been compiled. Running this:
gives this:
and means that the Ubuntu kernel that ships with apparently 12.04 and beyond does not support UDF filesystems fully. Arg!!! Filing a bug report on Launchpad right now...wish me luck.

Filed the bug report:

https://bugs.launchpad.net/ubuntu/+s...x/+bug/1537918