When it disappears again, take a look at the "online" tick box in the drive device data. It may be going offline, in which case the media will disappear (this is correct behaviour as you don't want to see media that is on a device that isn't currently available)
If so, then you need to troubleshoot why the system thinks the device is offline (just reticking the box will not fix the underlying issue!)
You should also see in the UpdateMedia log file whether UM can actually still see the files, but is marking them offline, or whether UM can't even see the files.
Things that spring to mind that could cause a problem are the autofs automouting is screwed up, the symlinks from /mnt/device to /home/public/data/etc are screwed up, or the storage device radar is having problems and thinking the device is offline... all should be fixable, but you need to determine the above first.
Collin, it has happened again. But this time, as per pigdog's comments, I watched very carefully what transpired before the failure. After adding several devices which required several router reloads, all was ok with the media drive. It was only when I had to reboot the core, with a proper shutdown, after the reboot, I then checked the orbiters and all showed the video and audio files missing.
I checked the device tree from admin and the drive was still shown as before. Checking the drive info data, the online box was ticked as to be online, but viewing the files from Admin-> Files & Media | Media Files Sync, there were no videos (movies), listed.
This whole setup is different than when I originally installed the core on 810-alpha2, and then aquired the 1.5TB drive to be added as a seperate media disk. When I originally set up the 1.5TB, I partitioned the drive and formatted for ext3, plugged it in, rebooted the core and it was discovered and asked the normal questions. I selected use it, all public, and it was then presented to me anytime I inserted a DVD for example, and chose to copy it. The system defaulted to it instead of the smaller OS drive and I copied the DVDs to the Public area. Never A Problem. Many router reloads and many Alpha2 updates and many Reboots of the core never destroyed the setup or the Orbiters/Media Directors from seeing and using it.
Also I remember that when I went into Admin-> Files & Media | Media Files Sync, the drive was listed on the left, without having to go into videos, under data, under public, under home. I just went into Admin-> Files & Media | Media Files Sync, selected the drive, ST31500341AS (sdb1)-CORE , selected show content, and all of my movies, for example, was there, both in the database and on the disk. Never a problem!
Only after having to reinstall the core, did problems begin to surface regarding the media drive, (sdb1). It has never been correct or reliable since then. I have tried to view UpdateMedia.log with several programs but it is so damm large, Kate, nor other, even windows programs, will open it. It's over 2gig large. I haven't deleted it yet, but I have copied it over my network and stored it on my on-Line drive for access by other Linux and Windows computers. If I looked into the (sdb1) drive with Dolphine I could then figure out what the original structure was because I don't remember it having the LinuxMCE structure vs. the Public, and it worked, flawlessly.
I've tried deleting and letting it be rediscovered several times, picking the LinuxMCE structure makes it work until a core reboot and picking the public dosen't even let it show up, period.
It's got about 190 DVD movies and a handful of cds ripped to it. To many to start over ripping.
Any help would be more that appreciated.