FireWire hard drives

[Derick Centeno]

On Sun, 24 Dec 2006 00:34:23 -0600
Paul Higgins <higg0008 at tc.umn.edu> wrote:

> Hi, Derick:
> 
> Happy holidays to you, too, and everyone on the list.  Speaking of
> the spirit of the holiday season, my niece is getting my G3 iBook to
> replace her cheapo eMachines PC that my brother bought her about a
> year ago, which just blew up. Yes, I'm putting YDL on it.  : ) 
> 
Great!

> As for the FireWire drive, I think I figured out what was going on.
> Take a look at the log again.  At first the system can't figure out
> whether there's a legit FS, but then it finds it.  The relevant lines
> are here:
> 
> > Dec 23 15:34:49 localhost kernel: EXT3 FS on sda1, internal journal
> > Dec 23 15:34:49 localhost kernel: EXT3-fs: mounted filesystem with
> > ordered data mode.
> 
> I'm not sure why the system gets confused at first, but clearly it
> figures things out, as farther down the log you can see that it lists
> the not only the correct FS, but also the correct vendor (Maxtor),
> drive size (250 GB), and interface (ieee1394). 
> 
Paul, I've been creating partitions and formats on all kinds of
hard-drives destroying, resurrecting and recovering data of all kinds
of complexity since the 70's.  Please believe me, if your system is
guessing and running through a laundry list of conflicting messages as
you've described something is not well.  

Computers don't guess anyway near the rational level you expect and
they certainly don't know enough to "figure" anything out thoroughly.
The way it (Linux) should work, is one clear output displaying exactly
what you have once and only once.  No "figuring" or maybe this or that.

In fact, because it behaves as you reported this, in my view, indicates
more complex problems:

* the hard-drive may not be recording bits of data properly.
* the Linux OS may not understand what the hard-drive is actually
reporting to it because the hard-drive hardware settings are not
standard or the firmware controlling the hard-drive is not talking
Linux in a standard manner.

I'm over-simplifying the possible issues, but the resolution is the
same -- force all the data on that drive to be zeroed or destroyed and
rebuild the data on that drive exclusively from within Linux using
fdisk and then mkfs.  Before you do that open up that drive and make
sure to double-check that all the necessary connections between the
hard-drive and the firewire enclosure you put it in are firm and that
there are no loose screws or anything else in that box.  Check all
hardware settings within the firewire enclosure and on the hard-drive
itself.  Make sure that there are no punctures or scratches that look
like they don't belong there.  There are many legitimate vendors, but
many more illegitimate ones unfortunately.

A large drive gotten at a "steal" of a price may be just too good to be
true.  The advantage to paying attention to all these nitty-gritty
details is that as you're experience grows you'll be less likely to
miss visible hints of something awry with the hardware and you'll get
more skilled in understanding what fdisc and parted and other similar
tools are telling you about these devices.  

Another annoying but still possible scenario is that it is still
possible to have unwrapped a completely new drive from a vendor who
received it pristinely wrapped from a manufacturer and it is still a
lemon, or non-working drive.

A drive which "mostly" works is really of no use to anyone.  I'm
assuming that you are rewarding, and not punishing, your niece in a
creative Addams Family manner.  So going the "extra-mile" to insure
that Linux sees everything on that drive the first time, and every
subsequent boot -- the same way -- without the funny talk or guesswork,
is your job.  I can only provide you with the suspicions I've developed
over the years to wipe out certain problems.  

The wonderful and powerful side of Linux is exactly what you are
mastering.  If this era were the 50's or 60's we'd be discussing
modifying our cars, instead.  No one would have thought it odd to have
detailed knowledge of axles, spark plugs, etc.  It was a fellow's job
to know what was going on with whatever one owned, and to know enough
how to use or repair it or what needed to get repaired.  Linux, is more
complex, granted, but the onus remains on the individual.

In my view, what makes Linux as an open source OS, so appealing is
exactly this -- when all of us are paying attention less and less
errors are possible and the OS itself gets better and better.  This may
mean each of us moves up the chain of mastery, a little, but it is
worth it.  Now if we'd only pay this much attention to our
environment....

> Anyway, I followed the instructions in that first link exactly, and
> everything went without a hitch.  I'm sure that mkfs was able to make
> a legit ext3 FS.

Suggestion:  Keep a notebook and record there exactly each step you do,
why and how.  Always cross-check against it, until you can do them
while you dream.  Get away from being "sure" about anything -- KNOW.

> It must have worked as I've been able to back up
> everything on the old iBook so far.  So the drive is basically
> working, just not as smoothly as I'd like. Maybe the kernel just
> doesn't like the cheesy Chinese-made FireWire enclosure I got from my
> local "whitebox" store...who knows?
> 
As far as firewire enclosures go, everything is pretty standard, unless
you didn't connect something firmly enough which means that the
connection is intermittent and therefore would itself appear to the
computer as "sometimes on" and "sometimes off".  All connections need
to be firm and secure.  Every nut and screw in it's proper place.

You're "the man", so don't be hesitant in insuring that every connection
is where it's supposed to be and function works as it should the first
time and every time.  The enclosure may be cheap; your effort however,
should be as "top notch" and focused as you can make it.

If after all that, the drive is not reliable -- it just may be that
drive.  One test which will isolate the difficulty further is to apply
the exact same above steps to a different drive placed into the same
"cheesy" enclosure, and see if Linux reports the drive's existence in
the same confusing way.  If Linux reports the drive's existence without
any of the "funny stuff" or "guesses"; the problem is unique to that
drive.

I guess by now you can figure out that I've several drives and
enclosures lying about my home so arranging this kind of test is not an
issue.  As for you however, use an expendable drive.  There is nothing
like being absolutely thorough.

> The thing that's confusing about that article I linked is that it
> says to make a new entry in both /mnt and /etc/fstab, while the YDL
> directions say only to create a new directory in /mnt and they never
> mention /etc/fstab.  I wish I knew enough Unix to understand why both
> things can work OK.
> 
These are not two different things.  fstab is a file within the etc
directory which can be modified so that it sees the new directory you
create within the mnt directory.

The difference is that the modification necessary within YDL 4.0 fstab
file is not necessary within YDL 4.1.  Why?  Improvements to the Linux
kernel are such that the Linux OS can make more assessments regarding a
working drive on it's own.  So the mastery of details necessary within
YDL 4.0 are less important, but remain an important foundation.  You
still need to be able to know the fundamentals discussed here to
decipher problems, but as you move up the versions of YDL the work you
need to do is a little less.  Just a wee bit.

> It would be nice if Linux could get plug-n-play working a bit more
> reliably when it comes to FireWire and Flash drives.  I find it
> pretty ridiculous that I have to mount a drive from a terminal, as
> nice as it is to have that particular skill.  (To be fair, however,
> YDL does a better job with Flash drives then does my Debian x86
> machine at work).  What would be ideal is for FireWire and Flash
> drives to automount once they have been properly formatted.  I don't
> mind using a CLI for formatting/mkfs at all, however.
> 
Remember that Linux is open source.  That doesn't mean convenience for
each individual initially but rather the potential for each individual
to have or create for oneself the tool one needs.  This is very
different according to what our needs become over time.  In this kind
of system someone creates a tool -- such as parted, fdisc, mediacheck
and others initially useful to themselves, it is posted as a GPL tool. 
Then I or you or someone else uses it for our own reasons etc.  We each
however need to come to improve our understanding of those tools and
their proper use.

As our individual sophistication grows, our projects and interests, as
well as what Linux can accomplish also grows.  However, like all such
human endeavors successful and complete coverage will be spotty.  After
all, broadband connections where throughput greater than 7MB/s is not
quite universal yet, is it?  Some towns don't have even enough
electrical power to run a radio station!

Just like most things, open source, means what you want it to mean
according to the value you place upon it, given the skills you have
which allow you to use it better.

> Now I just need to see if copying over my KMail directory works
> properly when going from YDL 4.0.1 to 4.1.  And that reminds me of
> another pet peeve: there doesn't seem to be any easy way to copy
> stuff from /home to the FireWire drive using the GUI.  I have to use
> the CLI for that.  It's not that difficult, but it is inconvenient.
> 
> -PRH

It is very difficult to design an open source gui which addresses
everyone's needs which is why the really powerful opportunity of open
source in my view is the potential to contribute to these various
desktop projects by letting them know what's important to you.
However, the problem in this discussion is understanding history.

The CLI is very much older and much more flexible than any gui because
of the necessity to execute commands quickly and explicitly while
determining what processes where in execution by a system. In
fact, it can be demonstrated by anyone with sufficient expertise that
more can be accomplished from within Apple's Darwin using the terminal
app than can be accomplished using OS X!

The difference can be imagined this way:

Anyone can open one or more terminals within Unix/Linux without a gui
and still get essential work done.

This cannot be done in either Windows or the Mac OS, as each of those
operating systems require that the entire Windows or Mac gui
portion of the operating system exist along with those terminals.
Solaris, probably could do this as Solaris is essentially Unix in the
first place.