Jerry Peters wrote:
> Gary Dale <garydale@rogers.com> wrote:
>> Jerry Peters wrote:
>>> Gary Dale <garydale@rogers.com> wrote:
>>>> Gary Dale wrote:
>>>>> Jerry Peters wrote:
>>>>>
>>>>>> I've never had any problems, other than DVD-RAM tends to be slow and a
>>>>>> large amount of buffered writes tend to build up (fixed by mounting
>>>>>> with the sync option).
>>>>>>
>>>>>> What's the "trouble" with working with UDF? My DVD-RAM mounts on
>>>>>> /dev/sr0 in rw mode and I copy data to it, just as if it were a large
>>>>>> floppy. That's the advantage of DVD-RAM over the other DVD whatevers,
>>>>>> it behaves like a large floppy, no special formatting required.
>>>>>>
>>>>>> If you really must use growisofs, get the source and change it to your
>>>>>> needs then.
>>>>>>
>>>>> I actually just tried using UDF directly and I found what the problem
>>>>> is. :)
>>>>>
>>>>> It appears that there is a bug in UDF support that isn't fixed until
>>>>> 2.6.22 (this is from the Wikipedia -
>>>>> http://en.wikipedia.org/wiki/Universal_Disk_Format) that limits you to
>>>>> file sizes of no more than 1G. I tarred and zipped the files before
>>>>> backing them up to save space (even then the tarball is almost 3G), so
>>>>> my backups failed.
>>>>>
>>>>> Still, the growisofs problem of wanting a clean disk bugged me, so I've
>>>>> switched over to ext2 for now. I test for a file system by trying to
>>>>> mount it as ext2. If it fails, I format it then mount it.
>>>>>
>>>>> Of course, this is not the file system anyone expects on a DVD-RAM disk,
>>>>> so I will give UDF a try again when Debian/lenny becomes the new stable
>>>>> release in a couple of years.
>>>> I'm back to about the only method that seems to be reliable.
>>>> - mkudffs /dev/dvd -- to blank the DVD-RAM so growisofs will use it
>>>> - growisofs -Z /dev/dvd /backups
>>>>
>>>> For some unknown reason, mke2fs /dev/dvd fails, or if it succeeds, it is
>>>> unreliable for writing. I may or may not get a complete cp /backups/*
>>>> /media/dvd but even if I do, I may not be able to mount it again. And
>>>> even if I can mount it again, there is no guarantee that subsequent cp's
>>>> will work.
>>>>
>>>> In short, working with DVD-RAM seems to be an exercise in frustration
>>>> even though it is the only game in town for doing repetitive backups.
>>>> It's supposed ability to be usable just like a hard disk is a myth, at
>>>> least until kernel 2.16.22.
>>> Never tried ext2. I do use some vfat formatted disks because Win98
>>> will not consistently recognize UDF DVD-RAM disks (it does recognize
>>> DVD-ROM's however). Never had any problems except that vfat on DVD is
>>> slow, of course vfat is slow on a large HD too.
>>> Could you be having some incompatablity problems with the DVD drive
>>> itself? Ext2 should work, and modern drives are supposed to handle bad
>>> sectors internally.
>>>
>>> Jerry
>> I thought perhaps the issue was one of having to do an eject between
>> operations but my testing gave me similar results with or without an
>> eject. The main difference is that sometimes it takes two mounts after
>> an eject - I guess mount times out a bit too fast. This makes testing
>> for a successful mount a little trickier.
>>
>> I'm going to stick with growisofs for now, unless it starts giving me
>> headaches. If it does, I'll try vfat.
>>
>> Thanks.
>
> I have 2 different DVD drives, one's a Matsushita and the other is an
> LG. I have a number of DVD-RAMS that the Matsushita has trouble
> recognizing (the light blinks seemingly forever) while the LG drive
> recognizes them without any long delays. I had considered these disks
> as defective until trying them in the LG.
>
> Jerry

I insist on LG drives. I've found them to be reliable. Other drives that
I've had have all developed problems fairly quickly. Plus, LG has had
DVD-RAM support for a long time, while other drives frequently don't.

In this case, it is an LG drive that is giving me the problems. I may
have a disk gone bad because I can't currently get it formatted with any
file system I try. On the other hand, I may need to replace the drive.
I'm going to have go to the site and try the disk in a different drive.
There may be more than one bad disk, which would indicate a drive problem.