[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Now that I have working box, any problems with LVM?

I have been using LVM with debian/amd64 since I first set up the box, including the root FS - a relatively long time now. It is quite stable, I can tell you that much. I myself use reiserfs, which you can, along with LVM, resize online and so forth. It's not your only filesystem choice by any means; I won't get into that whole debate. :)

At the time I set up, the installer had menu choices for installing over LVM, but these were broken. I had to install on a non LVM partition, set up LVM by hand, and copy over (which wasn't so hard, really). Not sure if this is fixed in later installer releases.

You're always going to have at least your little /boot filesystem (containing your kernel and initrd) outside of LVM.

The tricky piece was getting the root filesystem in LVM; for that you need an initial ramdisk. For a while, there was a script to create one automatically for LVM1, but not for LVM2, so I had to build these initrd's by hand. Now LVM2 has a script, but it's kind of broken for amd64, since (for whatever reason, I'd love to know) when ia32 libs (in or out of chroot) are in your library path, they pop up as dependencies of major, presumably non-ia32 binaries when you ldd, and that causes the LVM2 initrd creation script to copy them over (clever), but then the non-standard library paths are not searched (even when I create an /etc/ld.so.conf on the ramdisk, by the way - figure that one out). Then some important binaries can't link and you wedge. So before you run the initrd creation script, you may as well move your /etc/ld.so.conf aside and run ldconfig first.

Overall it's about remembering, too, that everytime you rebuild your kernel image packages you have to go through this procedure and create a working ramdisk, along with a custom grub/menu.lst that uses it. Of course the debian kernel image scripts wipe out whatever grub configuration you have in place and replace it with the generic one that won't work...

But all in all, once you get it working, it's quite good, and I believe you do see a good performance benefit with, for instance, LVM striped across two SATA drives. And of course you get all the regular benefits of LVM if, for instance, you add a third drive, etc.

If you're interested in doing this, I can email you sample configs and other details...

On Wed, 15 Jun 2005, J.A. de Vries wrote:

Hi list,

I was considering to use LVM on my brand new box now that is working. I
have never used it before, but want to learn about it. (How's that for a
reason? }:-) Before I start this little endeavor I'd like to ask if
anyone knows of any caveats of using LVM[12] on debian-amd64. Also what
are the feelings on the list of adding root to LVM? This is not a
critical box in any way, but as it is supposed to be a server stability
is of some concern.

Grx HdV

To UNSUBSCRIBE, email to debian-amd64-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org

Reply to: