SCSI error on write

[Basil Chupin]

On 13/03/12 02:15, Thufir Hawat wrote:
> On Tue, 13 Mar 2012 00:00:21 +1100, Basil Chupin wrote:
>
>> On 12/03/12 22:48, Thufir Hawat wrote:
>>> On Mon, 12 Mar 2012 22:08:58 +1100, Basil Chupin wrote:
>>>
>>>>> gnomebaker output (good for one month):
>>>>> http://pastebin.mozilla.org/1515313
>>> [...]
>>>> Why do you think that these are errors?
>>> Gnomebaker says "SCSI error on write", and the resulting disc is
>>> unreadable in either optical drive; the other info was just what I know
>>> about that particular drive.
>> My apologies - I did not not notice the screengrab in your post.
>>
>> I am a bit puzzled by you mentioning that you are using gnomebaker and
>> yet the log in that screengrab is showing brasero.
>>
>> However, how old is this /dev/sr1? It only writes to CDs and not DVDs as
>> well which indicates, to me at least, that it is pretty old.
>>
>> Have you cleaned the laser lately (using a special CD designed for this
>> task)?
>>
>> Have you tried using the slowest possible write speed (a high speed
>> often creates coasters on some writers)?
>>
>> Are you using a reliable brand of CD discs?
>>
>> (I must admit that I have never used brasero - well, I did try it a
>> couple of times but gave it up as a bad joke - and always use k3b which
>> has never failed me yet.)
>>
>> BC
> I removed brasero, so it's just some artifact that it shows up in the
> log.

Ce? You removed brasero but the log still comes up with brasero even 
though you are actually running gnomebake? Something not quite rught 
here........

In any case, why did you remove brasero when it is a better product than 
gnomebake? Look up the Wikipedia about both of them.


>    The CD-R media is generic, and, yes, the drive is rather old.  I'm
> going to try burning some more discs in a bit.  I'll bring down the burn
> speed.
>
> I'm holding off on upgrading the drive for now.  There's no real point in
> upgrading the drive, though, if the cables or something are wonky.

I thought that it is a cable - but you can always unplug the cable and 
plug it back in; doing so will probably slightly clean the contact area 
between the male and female parts of the cable and break any oxidation 
which may have occurred over time there. Doing so will also ensure that 
the cable is sitting firmly in place.

As you now confirm the burner is rather old which would also mean that 
its UDMA is pretty slow and since you don't mention what sort of a 
system you have it may also mean that slowing down the speed of the burn 
may improve things as the writer may not have sufficient buffer space to 
handle the data it is receiving to burn.

What you also have not mentioned is when did this problem develop? 
suddenly or over time? and only with certain brand of CD or with certain 
data? Only asking as it may give you the hint that you need as to why 
you are having this problem. (But I would start with bringing back 
brasero and retiring gnomebake.)


> If it were a dirty lens, wouldn't it give a different sort of error, not
> SCSI?  Just thinking out loud.

I wouldn't worry about the use of the word SCSI. As I mentioned, all 
devices are now termed SCSI and have sdX or srX for labels. (There are 
some applications which have default settings which use /dev/cdrom or 
/dev/dvd in which case one has to create symlinks pointing, say, 
/dev/dvd to /dev/sr1.)

BC

-- 
The vulgar crowd always is taken by appearances, and the world consists 
chiefly of the vulgar.
               Niccolo Machiavelli