On Mon, Jun 08, 2009 at 04:01:41PM -0500, Boyd Stephen Smith Jr. wrote: > In <20090608200757.ga26...@m364d1.ece.northwestern.edu>, Zhengquan Zhang > wrote: > >Now I would like to follow other list member's advice to have separate > >LVs for var, tmp, home etc. But I don't know how to perform the > >operation to make it happen, I have skimmed lvm howto but I don't see a > >chapter detailing on this task. > > That because it has nothing is particular to do with LVM. It is just like > splitting / into multiple partitions or across multiple disks:
It turned out I still don't understand the steps after I thought for quite a while. > > (0. [LVM specific] Create the new logical volume(s).) > 1. Create new file system(s) on the block devices. [LVM: logical volumes] > 2. Remount the original file system read-only. > 3. Mount the new file system somewhere temporary. > 4. Copy the data across. > 5. Unmount the new file system. > 6. Mount the new file system in it's permanent location. > 7. Remount the old file system read-write. > 8. Update /etc/fstab. > (Here you may want to reboot to make sure the system will do so without > manual intervention, to make sure your changes to the fstab are correct, and > to make sure any of the files that have been moved the the new file system > are no longer open on the old file system.) > > 9. Bind mount the old file system somewhere temporary. > 10. Remove the data from the old file system via the bind mount. > 11. Un- bind mount the old file system. > > Example: splitting / into / and /var: > 0. lvcreate -L 8G -n var debian I understand this. > 1. mkfs.ext3 /dev/debian/var I understand this. > 2. mount -o remount,ro / > (The above command probably won't work because some things are constantly > writing to [e.g.] /var/log. You might try something like: fuser -mk / && > mount -o remount,ro /. Or, you might just work from a system rescue disk.) I don't understand this. Why do I need to remount / read only? > 3. mount /dev/debian/var /mnt Why do I need to mount the lv to mnt? > 4. rsync -HaAxX --progress --stats /. /mnt/. So everything in / will have a copy in /mnt ? and because we have mounted var lv to /mnt. var lv has a copy of everything in / ? > 5. umount /mnt I don't understand this. > 6. mount /dev/debian/var /var So now var lv is mounted to /var and it now has everything in /var? > 7. mount -o remount,rw / Till here I am totally confused.. > 8. echo '/dev/debian/var /var ext3 relatime,acl 0 2' >> > /etc/fstab > (If you want: /sbin/shutdown -r now -t 5.) > 9. mount -o bind / /mnt > (Okay, so now /etc/fstab and /mnt/etc/fstab are the same file. However, > /var/log/messages is on the new filesystem and /mnt/var/log/messages is on > the old file system.) > 10. rm -rf /mnt/* /mnt/.[!.]* > 11. umount /mnt Sorry Boyd I don't quite understand, but thanks for your detailed reply and I would greatly appreciate it if you can still help me to understand it. Regards, Zhengquan -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
