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<TITLE>The Answer Gang 89: The Journey to Journaling</TITLE>
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<H3 align="left"><img src="../../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>The Journey to Journaling</H3>
<H4 ALIGN="center">pack your fs' diary seperately</H4>
<p><strong>From Licht B&uuml;lb
</strong></p>
<p></strong></p>
<!-- ::
The Journey to Journaling
~~~~~~~~~~~~~~~~~~~~~~~~~
pack your fs' diary seperately
:: -->
<p align="right"><strong>Answered By Dolavimus the platypus, Pretzel, Virtual Beer, Konqi, Tuxedo T. Herring,
Swirl, corncob Pipe, the Scissors, Amanda the Panda
</strong></p>
<P><STRONG>
Hi Gang.
</STRONG></P>
<P><STRONG>
I'm fiddling on my laptop again (almost all things are working) trying to
get s-video out working. In the course of this fiddling I'm raking wildly in
the bios which sometimes screws up the display (and I am still able to login
via ssh) or the machine freezes. Then I have to "push the button" and -
since I was forced to use ext2 (ext3 accesses the hd every 5 secs -&gt;
spindown and therefore power saving impossible) I have to wait quite some
time for the fsck to finish with my 10 GB root system (yeah, now I know why
to have multiple partitions..). So,
</STRONG></P>
<P><STRONG>
does any of you know a jounaling fs which plays nice with laptops? I googled
a bit, read stuff, but didn't find anything about it. I think I remember
someone here in the TAG saying that reiserfs had some patch to play nice?
Can someone confirm that?
</STRONG></P>
<P><STRONG>
Cheers and TIA
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Dolavimus]
I've been using rfs on my laptop since new two yrs ago with good results.
Although I haven't done anything in particular to address hd spin down for
power economy.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Amanda]
I have actually used ext3 with a recently installed <A HREF="http://www.debian.org/">Debian</A> "testing"
distribution. The hdd access can be "reduced" by installing "noflushd".
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
noflushd doesn't work with any j-fs. It says so on the web page.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Amanda]
However, I confess that I haven't really had a chance to fully examine
this issue. As regards partitioning the disk the following works well:
<TT>/</TT>, <TT>/usr</TT>, <TT>/boot</TT> as ext2 mounted read-only. Of <TT>/tmp</TT>, <TT>/var</TT> and <TT>/home</TT> which
need to be writable only <TT>/home</TT> really is usually large enough to require
journalling ( and sometimes <TT>/var</TT> ).
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I have tried several things over time: only one root and a small boot, full
monty with all dirs on seperate partitions and some things in between. The
prob with several partition: when you need some large space (naturally) none
is there on a single partition. Across two or more there would be enough...
Disadvantage of only one <TT>/:</TT> you can not unmount anything beforehand if you
know you gonna crash the system now... And a crypto-fs is hard to make then
too.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pretzel]
I think the very <EM>idea</EM> of a journaling filesystem makes "play[ing] nice"
impossible. Journaling filesystems <EM>have</EM> to access the hard drive on every
write. More accurately, they have to access the journal device each filesystem
write.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Well, it might be necessary for the j-fs to write to it's journal every fs
access, but ext3 writes to hdd <EM>every</EM> 5 secs, regardless of fs access or
not.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pretzel]
I think most journaling filesystem in Linux have an option for
journaling device which is normally on-disk but can be on any block device, at
least with ext3 and reiserfs. Some non-volatile memory would do nicely, but on
a laptop, I think the chances of being able to do this are almost nil.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I (as a not-knower) would have two ideas: a compact flash card in the pcmcia
slot and - RAM! In case of the RAM the journal would then be written to
hdd when also a normal hdd access takes place. True, this would be bad if a
system outage would occur without the journal having been rewritten to disk
but <EM>I</EM> would take these chances...
In case of CF, dunno if you can plug them in straight away or if you need an
adapter, but 16MB are really cheap anmd if you can save some power (-&gt; time)
with it...
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pretzel]
Doing it in RAM would effectivly make a journaling fs useless. What would be
the point then? That's the same effect as using a non-journaled filesystem.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Well, the journal would get written to disk with the data. If you use
noflushd then writes of the system (logging etc.) get postponed or get
written to RAM and then get written to hdd if a normal write (user
initiated) occurs. So, I dunno exactly how noflushd does this but when it
redirects the writes to ram the journal entries (if they need to be made in
that case) should be written to ram too.
</STRONG></P>
<blockquote><IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Scissors] This isn't so much "writtem to RAM" like scribbled in a ramdisk - it's
more like being hidden in the RAM of a caching controller. That's all
noflushd does, is allow some buffering at the filesystem-driver level.
So if something really does have content for the disk - and yes, that
includes its journals - it's either got to hit the disk eventually, or
you get to bear the risk that something might fail before it does.
</blockquote>
<blockquote>But the whole point of having a journal is to have it still be present
after a reboot event made something which normally isn't volatile space,
lose its cookies. Having a journal that isn't allowed to do its job
just complicates matters. Ergo, it shouldn't be put on volatile RAM.
</blockquote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pretzel]
Another possiblily compiling a kernel with magic sysrq support, if the machice
isn't totally frozen, you could do an emergency Sync/Unmount/Reboot.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
OK, now I have to admit it: HOW THE HECK DOES THIS WORK? I read the stuff in
<TT>/usr/src/linux/docs/</TT> but as much as I gathered Alt-Print d should do
something? It doesn't in my case. I compiled this in (if it's only the Magic
SysRq key in Kernel hacking) some time (not in my current kernel I see now)
but then (I tested it) it didn't work.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pretzel]
Worked for me. (I say worked because at the moment I don't have it compiled
it.) Try Alt-Sysrq-&lt;magic sysrq command&gt; (all three at the same time.) I don't
remember if it needed all three at once or not. sysrq probably only says
"print screen" on some keyboards.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Yeah, the prob was all at the same time... Now it works.
</STRONG></P>
<blockquote><IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Scissors] At least part of the confusion is with SysRq - on some keyboards the
SysRq lives as a subfunction on another key. Thus for such keyboards
you'd also need the extra key that invokes the secondary keycode. Fn
maybe.
</blockquote>
<blockquote>When it works then you should be able to (for instance) press Z and get
a little help list. In fact any character that doesn't do something is
supposed to show the little list. What I'm not clear on is "get outta
sysrq mode"...
</blockquote>
<blockquote>I've sometimes seen a console get into a state where it would respond to
Magic SysRq, but it couldn't get out of that mode anymore. So I hope
you have some spare virtual consoles, if you are just using it to settle
something simpler than "telinit 6 doesn't work".
</blockquote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pretzel]
So, in summary: No.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/smily.gif" ALT=":-)"
height="24" width="20" align="middle">
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
A No? &lt;shout&gt; I DON'T ACCEPT NO "NO" ! &lt;/shout&gt; (yes, I've been in the
army..)
<IMG SRC="../../gx/dennis/smily.gif" ALT=";-)"
height="24" width="20" align="middle">
</STRONG></P>
<HR width="10%" align="left"><blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Beer]
Why not plug one of these USB memory sticks and keep the journals there? That
way the immediate access is only required for the USB device and not for the
actual HD.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Cool idea, hadn't thought of this one, although I recently bought one! &lt;me
stupid&gt;
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Beer]
Which one? I've seem that Sony ads -- but they tell a lot about some strange
cruft with user mangerment and cryptosoftware which suggest custom WinXX
drivers to my suspicious ears.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
The cheapest one I could find. It was 49 Euro, super slim and works like a
charm. I think I will use gpg to encrypt files on the thing and simply put a
win gpg version on the stick too.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Beer]
If I ask for a drive give me drive and not an encryption device where I can't
trust the encryption anyway....
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
True, true...
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Beer]
Might still need patches, but if the journal keeping actually
needs only access to the journmal file and is not accessing the HD
where the data are finally going anyway -- It might even work with existing
journal/kernel code.
</blockQuote>
<blockQuote>
Then on the other hand you want journaling for some testing period -- why is
power saving durting that time so important? You could always switch back to
unjournaled if power saving is important. ext2/3 in that case would be
easiest as a cleanly unmounted ext3 is mountable as ext2 without problems.
The switching between ext3 and ext2 might be done by boot options I guess.
(can you ask in a init.d script for boot options ?)
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Well, the case is pressing just now in this testing period. I just rebooted
and had a full fsck (with Ctrd-d at the end) just now and I really need a
j-fs NOW. But I like the idea of j-fs's generally so I would like to keep it
after the fiddling too. You are right that ext2|3 would work now but I am a
little bit burnt with that since I had ext3 in the very beginning, installed
the system (a lot) and then wanted to switch to ext2 (with removing the
journal) according to manual. But the ext-tools weren't current at that time
in testing|sid so this broke (!) the fs with FULL reinstall (some bad things
occured at the same time leading to this). But ext2|3 would be an option.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Beer]
I never tried to completely switch back to ext2 and delete the journals, but
I <EM>did</EM> mount ext3 as ext2 and nothing bad happened. I made sure they are
clean so.
</blockQuote>
<blockQuote>
On Laptop power save is only a real issue on battery -- then the sudden
crashes should not be that frequent unless you insist of fiddling around in
kernel space on the train.... So for some normal usage running on battery and
ext2 might be sufficient, but when you are on mains power you can switch back
to ext3. There must be a way to make this decission in lilo by some option
which is evaluated in init.d/boot*
</blockQuote>
<blockQuote>
Or check if you are on battery and make the decision based on that. Frequent
sleep/resume inbetween are then not that practical so.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Konqi]
For those living in Germany: Aldi has an 128 MB USB memory stick for 49.99
Euro next week, I read in an Heise announcement.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
And for those who want to know something about mine:
<A HREF="http://www.computer-cash-carry.de/ccc/index-ns.html"
>http://www.computer-cash-carry.de/ccc/index-ns.html</A>
see Festplatten IDE, there at the bottom (all german, just for the curious)
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Tux]
Any of you guys want to write up an article on what it takes to get one
working, or is it simple enough to describe in a 2-cent tip? I'd be very
curious.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
</STRONG></P>
<pre><strong>modprobe sd_mod
modprobe usb-storage
mount /dev/sda1 /mnt/usbstick
</strong></pre>
<P><STRONG>
<IMG SRC="../../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Tux]
Wow. Mondo cool. I love Linux.
<IMG SRC="../../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</blockQuote>
<blockQuote>
I think that there's a USB memory stick in my near future...
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I wonder if what I have
<A HREF="http://linuxmafia.com/~rick/linux-info/easydisk-memorystick"
>on my website</a>
is sufficient for a 2-cent tip? I can re-write it, if it's considered too
half-assed. Here's the relevant excerpt:
</blockQuote>
<blockQuote>
USB on Linux seems a bit... different, especially since I'm not really
used to devfs-type things.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Beer]
The only thing I ever tried was a digital camera (Olympus C100 zoom) and it
needed a kernel patch (usb-driver) to be properly recognised. Apart from that
the camera works as a disk as expected.
I mount <TT>/dev/sda1</TT>, it will be rw right on the first mount, no need for
remounting.
</blockQuote>
<blockQuote>
So if you really <EM>have</EM> to go through all this remounting, you can't fdisk
the thing into partitions, etc. It really seems strange.
</blockQuote>
<blockQuote>
I do remember that zip-drive "problem" -- the win programs to access it
partition it to use sda4 instead of sda1. So this might all be very specific
to the hardware and drivers used (or used the first time the disk was
partitioned).
</blockQuote>
<blockQuote>
But basically these memory sticks seem to work, then I'll keep my eyes open
for one.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I've been figuring out how best to deal with
it on my laptop, since my wife gave me a 32 MB Easy Disk "memory stick",
a cute little plastic thing on a keychain fob.
</blockQuote>
<blockQuote>
I'm still working it out, but it looks like I need the usb-uhci and
usb-storage drivers (impliedly also usbcore), at which point I can do:
</blockQuote>
<blockquote><code><font color="#000033"><br> # mount -o rw,uid=1000,gid=1000 -t vfat /dev/sda /mnt/fob/
</font></code></blockquote>
<blockQuote>
(where 1000 is my own login account's UID and GID).[1]
</blockQuote>
<blockQuote>
The bizarre thing is: That command (or anything like it) always
returns:
</blockQuote>
<blockquote><code><font color="#000033"><br> mount: block device /dev/sda is write-protected, mounting read-only
</font></code></blockquote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [corncob Pipe]
I believe that this error is more of a "fail-safe"
than it is an annoyance...
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I banged my head up against that problem for a couple of days, and
"fdisk <TT>/dev/sda</TT>" kept insisting...
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Um, my usb stick has a small switch on it's side to make it write-protected.
You don't have by chance missed that one?
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
That was part of what I spent some part of a couple of days, looking for.
No, there's no hardware switch. Moreover, doing a remount entirely via
software <em> _does</em> succeed in making it writeable, following the initial
mount. If the obstacle were a hardware switch, that would not have
happened.
</blockQuote>
<blockquote><code><font color="#000033"><br> # fdisk /dev/sda
<br> You will not be able to write the partition table.
</font></code></blockquote>
<blockQuote>
...until it finally occurred to me to do...
</blockQuote>
<blockquote><code><font color="#000033"><br> # mount -o rw,remount /mnt/fob
</font></code></blockquote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
Does it? To me, the mount command references
"<TT>/mnt/fob</TT>" (unless of course, "<TT>/mnt/fob</TT>" points to
"<TT>/dev/sda</TT>"???)
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
The point is that the <em> _original</em> mount command, which gets re-mounted
here, uses <TT>/dev/sda</TT>, <em> _not</em> <TT>/dev/sda1.</TT> I'm trying to stress that at
least <em> _some</em> memory sticks must be addressed as if they were SCSI-based
<em>floppy</em> drives. No partition numbers, you see? This was non-obvious
point #1.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
What you have done here it to re-mount in in "rw"
mode, yay!
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
Um, yes. That's exactly my point. The necessity to do so was
non-obvious point #2.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
Notice that the mount command references <TT>/dev/sda</TT>, instead of <TT>/dev/sda1.</TT>
That's the other odd thing: I kept had no luck until I happened to try
/dev/sda.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
I think this is as a result of the way in which device
files are referenced under Linux
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
Well, where were you when I was trying to mount the device, the first
time?
<IMG SRC="../../gx/dennis/smily.gif" ALT=";-&gt;"
height="24" width="20" align="middle">
</blockQuote>
<blockQuote>
I'm saying _the point is non-obvious_ because many other instructions
one finds for mounting similar devices tell you otherwise, because
intuition suggests that a memory stick ought to be addressed like a hard
drive, such that it can have multiple partitions, and because it's the
first time in a decade of addressing SCSI devices on Linux that I've
<em>not</em> put a number after <TT>/dev/sda.</TT>
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
Oh, <EM>now</EM> I see what you meant. I mis-interpreted you
the first time.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
My guess is that the Easy Disk is being addressed as if it were a floppy
disk instead of a hard drive partition, which is why it's sda instead of
sda1.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
Hmm, I don't quite follow you here. Why would a HD
partition not utilise "sda1" if told to do so?
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I'm not sure what's the nature of your confusion: Are you willing to
simply take my word for it that addressing <TT>/dev/sda1</TT> on the memory stick
absolutely does not work, and that addressing <TT>/dev/sda</TT> does? That would
make this conversation a great deal easier.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
Oh, I'm not doubting you one bit, I just mis-read your
sentence, I'm sorry, Rick.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
And I believe you're missing my point: Because the Easy Disk is (it
seems) classed as functionally the same as a floppy disk, there is no
concept of partitioning, and thus no partition numbers.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
And if
Easy Disk were being addressed as a floppy then it
ought to use "<TT>/dev/fdx</TT>" in this case, surely?
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I beg your pardon, but no. That wouldn't be SCSI then, would it?
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
It would, it would.
</blockQuote>
<blockquote><IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Scissors] I seem to recall that normal floppy disks used in an IDE-chain LS-120
bay are still accessed by the fdx mechanism. However the one around
here lost a pin so I can't check.
</blockquote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I hope you're not under the impression that there aren't all Linux
floppy disks must be addressed as <TT>/dev/fdx?</TT> SCSI ones are <TT>/dev/sdX</TT>,
and parallel-port ones are <TT>/dev/pfN</TT> . Neither supports partitioning.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
!
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I have no idea why Linux always mounts it read-only, though.
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
Me neither.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I have no clue what it is recognised or attached like, but in my case I have
to use <TT>/dev/sda1</TT>, else it will make trouble.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
Yes, I've heard such reports. That is why I have concluded that some
USB memory sticks are recognised as quasi-floppies, and some as
quasi-hard disks.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
I guess there are two (or more) controller producers and there comes this
trouble.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
If by "controller" you mean the USB chipset on the motherboard, I very
much doubt that, because the difference seems specific to the add-on USB
storage device, not the USB host.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
No, I didn't mean the host, I meant the usb controller in the sticky. These
need some controller too, don't they?
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
They need some sort of USB circuitry, and, to be sure, differences in
such circuitry seem to have caused these differences in mode of
operation between memory sticks. Whether it's common to call that
circuitry a "USB controller", I am unsure, but such was not my
impression.
</blockQuote>
<P><STRONG>
<IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Maybe there are even patents involved so that the other producer
had to take a different approach (and maybe this also helped in case of
"booting off floppy -&gt; off usbstick).
Anybody anything about the subject?
<IMG SRC="../../gx/dennis/smily.gif" ALT=":)"
height="24" width="20" align="middle">
</STRONG></P>
<P><STRONG>
But there is a strange thing:
sometimes there comes a error message saying that there is (can't rememeber
what) wrong, then I try to mount <TT>/dev/sda</TT>, this will fail, and then I can
mount <TT>/dev/sda1</TT> - So much for deterministics.
</STRONG></P>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Pipe]
Unless of course this is as a result of
the Kernel's divine intervention??? Va savoir??
</blockQuote>
<blockQuote>
<IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
> [Swirl]
I'm ultimately less interested in kernel psychoanalysis than in making
it do what I want, thanks.
<IMG SRC="../../gx/dennis/smily.gif" ALT=";-)"
height="24" width="20" align="middle">
</blockQuote>
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