Re: Unable to reread SCSI optical disks

[Giuliano Pochini]

> I have an old MaxOptix optical drive that has been used for years
> [...]
> My problem comes when I unmount the disk, eject it and insert a
> different disk. It appears to mount ok but when I look at the
> data it has the directory structure that was on the old disk
> [...]

Again this problem :-(  Some devices don't send the signal UNIT_ATTENTION when
the disk is changed, so Linux don't know it has to flush the caches. I had the
same problem with my M/O drive, then I discovered that a jumper can
enable/disable that signal...
You can solve the problem trying to mount the device while no disk is
inserted. The failure will force a call to  invalidate_buffers() (see
sd.c:check_media_change()). Then insert a new disk; it should work fine now.

Bye.