LVM Logical Volumes viewing partitions, mounting, creating, sda moved to sdb

[Christopher Chan]

On Friday, May 14, 2010 03:44 PM, giovanni_re wrote:
> KU 10.4.  Desktop with2 hdisks. 1.5TB has 9.04, was hda/sda. Now install a 2TB as sda, move old disk to sdb.
>
> Alternate install 10.4 on the 2TB sda.  Grub finds the 9.04 install on sdb,&  installs fine on sda.
>
> Both installs have a /home partition in their sda4 logical partition, probably sda5 on each drive when they were installed.
>
> 10.4 boots fine on the 2tb, but 9.4 refuses to boot off now sdb.
>
> Less important question:  Suggestions for getting the 9.4 to boot when that drive has been moved from sda to sdb (data connector on the motherboard).  It's probably a mount issue?

You need an entry in grub.cfg for the Jaunty installation. Do you have 
one that does not work or none at all?


>
>
> ==  How does one see the logical partitions??
>
> fdisk -l,&  parted -l,&  gparted, I have used - a few days ago, so I don't recall the specifics right now.

fdisk -l (with root permissions)


>
> IIRC, on 9.04 as sda, gparted would see the LVs,&  show some info about them.
>
> When I boot 10.4, IIRC gparted doesn't pull up any info about the LV's, even on the sda drive with the 10.4 os it booted from. :(
>
> IIRC, none of those programs show info about the LV's on sdb, which has the 9.4 install on it.

No comment on parted. I don't


>
> So, is LVM properly supported in some partition creation/diagnostic sw??? ex: fdisk, parted, gparted?  Is there some other program that will at least see,&  perhaps show some info about those partitions?

lvdisplay

>
> How about creating more LVs in the free space on the drives?  What sw can do that from the running 10.4 system? (ie, I don't want to have to use the alternate installer disk to do partitioning, now that the os is installed.  I'm hoping that is possible - hasn't LVM been out for quite a while?  Why don't fdisk&  parted support it properly yet?  BTW, what orgs create&  support the LVM sw? GNU? Linux Kernel?? Other?

fdisk/parted/gparted are used for creating partitions only.

You then need to use pvcreate to assign partitions or a partition to a 
physical volume. Then you need to assign that physical volume to a 
volume group with the vgcreate command. Finally, you carve the volume 
group into logical volumes with the lvcreate command.


>
> ==
> Most Important:  How can I get 10.4 to be able to see&  mount the 9.4 /home partition which is now on (probably) sdb5?  What info will be needed by the mount command? UDEV #?  What sw (parted, fdisk,???) will show the info necessary to use in the mount commnad??

fdisk -l

As for mounting:

eg: mkdir /oldhome; mount /dev/sdb5 /oldhome

Add an entry in /etc/fstab if you want it done each time the computer boots.