ADDING data filesystem to the ROOTVG (good or bad)

ADDING data filesystem to the ROOTVG (good or bad)

Post by Steve Wambol » Wed, 13 Feb 2002 03:39:04



We have a PSeries machine with 2 18GB DISKS,     I have the rootvg on HDISK0
, I also wnat to add a filesystem to HDISK0 and have it use 11GB (the
filessy name will be /usr1) .    However I don not want /usr1 to be part of
the ROOTVG.  The question is .. Can I put a filesystem on the same "physical
disk" as rootvg without the filesystem being part of rootvg

thanks

 
 
 

ADDING data filesystem to the ROOTVG (good or bad)

Post by Steven Langdal » Wed, 13 Feb 2002 04:48:35


On Mon, 11 Feb 2002 13:39:04 -0500, "Steve Wambolt"


>the ROOTVG.  The question is .. Can I put a filesystem on the same "physical
>disk" as rootvg without the filesystem being part of rootvg

Sorry Steve, no.  The whole disk is in the VG.  If you wan't to create
an FS in another VG you will have to get another drive.

Regards

Steven

 
 
 

ADDING data filesystem to the ROOTVG (good or bad)

Post by Steve Wambol » Wed, 13 Feb 2002 05:22:42


Ok -- Thanks for the info ; As a follow up question.    If I have TWO
filesystems I want to create, /usr1 and /usr2   one of the filesystems will
go on hdisk1 and the other (/usr1) will go on hdisk0 along with rootvg. The
question is, My /usr1 filesystem, we see much more activity then /usr2, with
that in mind do you think it would be best to put my "least" busy
filesystem as part of rootvg or does it matter. Bottom line is I will have 2
filesys and one of them will have to go on the 18 gb rootvg disk.

Thanks.


> On Mon, 11 Feb 2002 13:39:04 -0500, "Steve Wambolt"

> >the ROOTVG.  The question is .. Can I put a filesystem on the same
"physical
> >disk" as rootvg without the filesystem being part of rootvg

> Sorry Steve, no.  The whole disk is in the VG.  If you wan't to create
> an FS in another VG you will have to get another drive.

> Regards

> Steven

 
 
 

ADDING data filesystem to the ROOTVG (good or bad)

Post by Steven Langdal » Thu, 14 Feb 2002 04:01:17


Steve - I'm sure your aware, it's always best practice to keep rootvg
for OS stuff only.  I take it you have a bit of a disk shortage?

Having said that, I'd put the least active filesystem on the rootvg
disk, the rootvg disk will have activity already, it will also have a
swap volume on it too, you don't want it to become too much of a
bottleneck.  So it does make sense to put the busy filesystem on a
different disk.

Thanks

Steven

On Mon, 11 Feb 2002 15:22:42 -0500, "Steve Wambolt"


>Ok -- Thanks for the info ; As a follow up question.    If I have TWO
>filesystems I want to create, /usr1 and /usr2   one of the filesystems will
>go on hdisk1 and the other (/usr1) will go on hdisk0 along with rootvg. The
>question is, My /usr1 filesystem, we see much more activity then /usr2, with
>that in mind do you think it would be best to put my "least" busy
>filesystem as part of rootvg or does it matter. Bottom line is I will have 2
>filesys and one of them will have to go on the 18 gb rootvg disk.

>Thanks.

 
 
 

1. When good filesystems go bad...

(Apologies if offtopic; I couldn't figure out where else this should
go.)

To start:  Running SuSE 7.0 with kernel 2.4.3 on a T-bird 850 with a VIA
686 chipset, using ReiserFS for all partitions.  About 2 weeks ago, had
some sort of odd machine-freeze which left a big chunk of zeroes at the
end of /var/log/messages.  Didn't think too much about it, just rebooted
and the machine seemed fine.

Now ReiserFS is a good thing... except when it goes bad.  No need to
fsck, great performance, etc.  So, what happens when you get a string of
kernel OOPSes related to ReiserFS?  My plan was to restore from backup,
until I realized I didn't have the KDE2 binaries or libs backed up, and
slurping ~40M of RPMs across a dialup connection is painful.

Booted from the SuSE rescue CD, then ran reiserfsck.  It exited with an
error to the effect of "couldn't open journal."  Ground my teeth,
grabbed my laptop, used it to download the latest versions of the
ReiserFS tools from http://www.namesys.com/ .  Stuck the binaries of the
tools and their manpages on a floppy, then ran reiserfsck from the
floppy.

"Wow, look at all the errors it's outputting!  Things must have been
seriously damaged."  Reboot the machine.  Problems persist.  Read man
page again, realized that reiserfsck is totally different from e2fsck.
Tried again from the rescue system, using the -x option to reiserfsck.
("Fix fixable errors")  This time, the output indicates that there were
problems on /var and / .  Yikes.  Reboot again, trusting that all is
well.

Nope.  Try rescue system for the 3rd time, run reiserfsck with the
--rebuild-tree option ("Try to rebuild filesystem from scratch.")  Yep,
there were bad problems with / .  Finally, everything is working right!

...Or not.  Booting normally coughs up "/dev/null:  Not found".  AARGH!
Boot rescue system for the 4th time, comb through /dev for mangled or
missing devices.  /dev/null and /dev/dsp* all existed, as character
devices with major and minor numbers of 0.  Used mknod to recreate them.

Finally, the system boots normally.  I'm not sure if I trust it though,
and will restore from the aforementioned backup once I've gotten those
KDE2 RPMs and put them somewhere safe.

The practical upshot:
0. Don't Panic
1. Make Backups Frequently
2. reiserfsck is not as straightforward as e2fsck
3. There may be problems even with 2.4.3 and the VIA686 chipset.

Hope this helps someone....

--
Matt G|There is no Darkness in Eternity/But only Light too dim for us to see
Brainbench MVP for Linux Admin /  Workin' in a code mine, hittin' Ctrl-Alt
http://www.brainbench.com     /   Workin' in a code mine, whoops!
-----------------------------/    I hit a seg fault....

2. Stylewriter II and lpr

3. bad partition on good disk won't mount or fsck (bad magic number/superblock)

4. Corrupted .bash: How to recover?

5. Filesystem semantics protecting meta data ... and users data

6. How to restore partition table with gpart?

7. How do you add a bad block to e2fs bad block list?

8. Volume Manager

9. ROOTVG going bad -HELP

10. How to remove a hdisk which is not belong to rootvg but has a rootvg label

11. hd3 outside of rootvg is bad news

12. About mirror rootvg and the contents in the rootvg automatically synchronize

13. Replacing bad rootvg disk...