[linux-lvm] Release practice - was: Another strange setup by a newbie, but strange oops resulted while trying vgextend/vgmerge!

[Daniel Mitzlaff <hackbyte@gmx.de>]

Hello AJ Lewis...


I wrote
>> BUT, all my drives are filled up with data, there's NO BACKUP(!), and no
>> way to take more than a single drive free for reformatting.

From AJ comes:

>If this is a production system, you should really should have some 
backup.

Hey, i'm a little bit nerd/geek, really far away from things declared to 
be "normal", *but* *not* *stupid* ;)

>There are plenty of things that can go wrong without even putting layers 
like
>LVM into the picture. I agree that upgrading LVM should not mess up 
you're
>data, but if you have no backup, you are taking a lot of risks no
>matter what. I do understand that for home systems backup is a difficult 
issue,
>but bad things do happen even with the most finely tuned systems.

Yes, i just got a - i really can't see from where it comes - crash, lost 
my complete /home/hackbyte, /home/ftp and /home/lost+found, all other 
files still remaining to be there, 'debugfs lsdel' reports a regular 
delete on all these files (34000 files in 7gig!). This harddrive is just 
taked into my bed,  waiting for some day when i can get my files back, 
INCLUDING the filenames, 99% of the files are still there and recoverable 
;).  Do you now believe me if i say i know what i do?;)

>CD burners are a cheap and effective way to backup user data, and hard 
drives are cheap
>enough now that you could buy a cheap external drive with large capacity 
todo
>backups to. That said, it is very unlikely that you will loose data to 
LVM.
>ven the issues that have come up on the list don't cause data 
corruption.

;) - i just have to smile a little bit. Please tell me how i can backup 
my data on CD if i had a filesystem, splitted in 5 partitions, 90% of the 
space filled with data? If you know a way to backup all these data like a 
streamer does, on CD, please tell me *soon*! Even if i try tar -m, i 
can't get all the data. And i don't see a reason how i should implement 
another structure, only to backup all the files. (Hhhm, only installing 
lvm eventually, ok sorry, just joking;)

Hhhmm, about data loss or data corruption, while testing lvm0.9 on 
vanilla 2.2.18, i got more than once errors unmounting /, once of these 
followed by a lost vg. I can't reproduce this, but i've seen another user 
with a lost vg on the ml. Ok i'm sure that's a worst case condition. But 
if it can happen while i test it, so it can happen if i run it! About the 
vg lost, just i think, at the time vgchange -a n updates the lvmtab, 
there's no sync between rewriting lvmtab and shutting down the system, 
because / is still in use and can't unmounted at a point where no shell 
is left on the system. (please take this issue for your changes in the 
next time! vcfgrecover even doesn't worked - what the hell ;)) .. as i 
said, i can't reproduce this ;( )

Next issue, on buying a cheap drive for backups. Hhhhmm, i just got a new 
45Gig drive to expand my space. That's the reason why i think about using 
lvm/raid or other things, don't wanting to split again my nirvana for 
another partition;) (ehm, yes i call my network and especially my fs my 
private nirvana so i hoped to got a vg called nirvana;)
If i had enought money to buy a new drive for mirroring, so i can go and 
let someone repair my dat-drive, nor?;)
Not that i think DAT is really easy to recover from, but it's the 
cheapest backup-solution i get (from old machines even;).

>Which patches are you talking about here?

Oh, i can tell you which patches i mean, look at the ML, a mail from 
Heinz ->

http://lists.sistina.com/pipermail/linux-lvm/2000-November/003698.html

[linux-lvm] Re: Some brokenness in LVM 0.9 (on 2.2.18pre23) [long mail w/ 
oopses and patch] 

..........


>First of all, if you are using the stock redhat packages, and they don't 
work
>with the new LVM stuff, please complain to RedHat. They are the ones 
that
>should deal with that.

That's NOT a redhat problem, lvm seems to work, only a few issues 
don't..... ;)

>Secondly, what are you talking about? --> "version that does not work" <--
>What is this? Are you using the RPMs off the sistina site? Did you 
compile
>the packages yourself? If you used the sistina packages, make sure the 
lib>lvm*
>files are removed from /lib. My initial packages installed into /usr/ 
instead

Eh? ... no comment............. see below

>of root. I will get new packages out shortly that correct this problem. 
I
>was hoping the transition issue would be resolved before I did this, but 
it
>looks like I need to get new packages out first and then deal with that.
>You can also look at >http://distro.conectiva.com.br/experimental/lvm/
>for a version of the LVM packages that supports both the old (0.8.x) and 
the
>new (0.9.x) interfaces.

Hey, cool. Very cool. Just imagine, i give you a light about which 
kernels i use, i just described the difference between a tarball and a 
rpm-paket, what the heck did you think what i do eh? ;) I explain..

First, it comes to me that i found myself in the happily position to buy 
a new drive. Thinking about reorganizing my files. I see, it wasn't good 
to split up again my files, so i decided to take some knowledge about 
optimizing this point. Just opened my favorite web-browser, going to 
www.linuxdoc.org, taking some howto's and beginning to read them. All 
these howto's tell me that raid wil not fit into my setup, because i 
can't reformat all my drives in one strike, so i see clearly that LVM is 
the choice.

Ok, then, i just looked a little bit around to understand what LVM want's 
to do with my data and drives, and it seems to be ok for me. I just 
wanted a linear append on all drives, if i can get striping, hey cool, 
but not really important. Only one thing is important - i have to resize 
the entire fs after freeing another drive to take it into the VG and the 
into the LV.

So i go to kernel.org, downloaded an actual linux, go to sistina.com, 
downloading an lvm - going to home, sit on my network - reading again 
install and readme files! - and began to work.

I've used a vanilla LVM0.9 from ftp.sistina.com, together with a vanilla 
2.2.17/18 tarball from ftp.kernel.org. Compiled all tools myself. Used 
vanilla "make install"  to bring it right now into my system. I even it 
is a vanilla RH6.2 installation. What do you think can be wrong on this? 
And, if there are something, don't you mean that this has to be explained 
in the README or INSTALL file? For what reason are these files written by 
-who want to know this now- eh? Oh, i forgot to tell that i asked SOME 
people on ircnet about my problems with lvm, most of the users tell me to 
DON'T even use it. - At this time i know why, and that it probably takes 
only to LVM0.9 - ***i hope***.

>Define stable. I don't know of any software package that is 100% stable.
>There are always issues to track down. Point releases, such as LVM 0.9 
are
>especially prone to that. You should know that. If you are concerned 
about
>it, don't upgrade immediately. Monitor the linux-lvm and lvm-devel 
mailing
>lists and see what problems people have. That's why we archive the 
mailing
>lists.

(smile), ok another piece of background. I'm not really a good 
programmer, but for a long time i maintained a bbs here in germany, 
writing and releasing my own tools to give my (and other sysop's) users a 
lot of experience which no other bbs has. Do you think i can see 
differences between stable and unstable software? Not? Ok i explain. If i 
can leave all my data right on the lvm, the lv still filling up - just 
for example with an audio-stream from my dsl line, and go to bed, w/o 
thinking any jota about how i can guard my data - knowing that all is ok 
in the morning (even if my fs with its 100Gig is filled up to 95% in the 
morning, from - in example - 70% in the evening before) - THAT is stable! 
At this point, i can't build a LVM - because resize don't work.....(And i 
don't want to imagine what can happen if i - for some cool reasons - 
implemented an automatically resizing over spare disks if the system 
grows to much w/o my presence... ok i just can't do it so because all 
drives are already filled - but this can be a worst case condition where 
lvm has to run w/o any problem!)

>Good, I'm glad you are reading the ML. We are working on the issues. 
Heinz
>has been out of contact for a few weeks due to a move and other issues, 
which
>is delaying feedback. Sorry about that. :(

Hey i said - i know what i do. And i really know how busy a programmer 
can be WITHOUT answering to questions how to use some - still documented 
- features or setups. Feedback is not really important, if all is 
described or self-describing *AND* working...

>I understand your frustration, but know that we are working on this.

Ooh, i really hope and can exclude all possibility of doubt - since 2.4.0 
is released;) - that someone urgently hacks around to fix these problems, 
oups, forgot that i read, the fixes are still there, but not released... 
(again -> no comment about this!)

>As I said earlier, most point releases have issues that need to be 
worked out,
>and LVM 0.9 is no exception. If you want a "stable" release, you
>should probably use LVM 0.8.1 for now. LVM 0.9.1 should be out soon, 
which
>should have all the *known* bugs fixed.

Hhhhmmm... hey guy, i think, it's not cool to be forced to test the 
software you just write.
I think there's NO REASON TO DON'T TEST IT YOURSELF!

So there is - in my eyes - NO WAY to take out a release that - as you can 
see - in vanilla don't run WITHOUT ANY COMMENT ABOUT THIS. Hey ok, LVM 
still works, but not in all pieces!

At this time, i don't know any frustration about your software, it's not 
fine that i have to wait - but that's life.
The only thing is, i liked to know it BEFORE I TAKE ANY EXPERIMENTS with 
this software!
And, even to say that LVM is for free, is no ticket to do it this way!

Just, think about the time i spend installing and testing a software 
which documentation never said anything about "absolutely beta for this 
release" or "possible bugs making it unusable in some cases". As i said, 
im not really a programmer, but i have to sit at the office for a big 
part of the day, just going home, late in the evening, working on my 
private network. Didn't you believe that there are other things to do for 
me, except to learn that LVM0.9 has bugs which makes it unusable for me 
and (i'm sure) a lot of other private users?

All over these issues, i think it's a shame that it happened as it did. 
Ok, there are several reasons how can things go that way wrong. BUT we 
all, especially people who works on software, had to do all what is 
possible to prevent us from such ..............(again, i don't say what i 
think - you know it already)

Cool ideas are very nice, and if it takes place on some mind - to be 
worked out in a usable state, then we all only got a benefit if the 
persons who are working on this idea right know what they do........ I 
just imagine what happens to the earlier linux kernels, if linus itself 
takes this way to release new kernels.

So, i go now into my weekend, still fiddling around with my partitions - 
giving you and all persons who work on LVM a lot of hints ;).

-->**NEVER** and not only i say, **NEVER** take out any untested release 
w/o issuing it in the manual.
-->**EVERY TIME** if you get patches, give it to the people who need it - 
and give a documentation where to find (again, cvs is not a thing who 
everyone can deal with)!
-->And in the future, do all what you can do that NO EVETUALLY KNOWN BUGS 
go to the kernel! - this is the most important thing for all 
OpenSource/GPL supporters!!!
-->Just, if you can, please urge as many betatesters as you can reach to 
test your release BEFORE it goes out to the world.

And, please try to make me happy with your next release, and with the 
following releases. I can only say that i - at this point - don't give 
any commets about lvm if i'm asked about this - except that it is smart 
to wait for the next release. In the other way, i see it to come, that 
every user or customer which ask's me about handling a big fs will hear 
from me that lvm can't be a choice...... (hey, that is not a thing who 
bothers you at this time, but image is image - and the image of LVM is 
not really good in the IRCNet)


Cya, and don't be angry about my mail, just take it, think a lot about 
it, and take some changes in the future ;)
(again, this goes to all lvm maintainers...)

Greeting - hackbyte aka hackbyte@gmx.de / hackbyte@hackbyte.de - IRCNet 
#linux.de, +linux.de
P.s.: Hhhmm sometimes, i'm wondering about my english, it seems to be 
readable, but if you think i really learned it @school - you're wrong;)
Und nochmal ein paar grüsse an unsere deutschen mitleser, ich bin echt 
verägert, aber so kanns ja nu wirklich nicht gehen ... ;)