Making space for another OS.

[Craig McLean]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


Bill Rugolsky Jr. wrote:
> On Tue, Nov 15, 2005 at 02:45:24PM +0000, Craig McLean wrote:
>> I'm going to stick Solaris 10 on my laptop (this is not an advocacy
>> post, just for info) and to do so I need to free up some physical space
>> on my disk which is currently allocated to LVM2.
> 
>> 5) with fdisk, delete the partition entry and recreate from same
>> starting block, but ending the partition ~10Gb short of where it ends now.
> 
> This will almost certainly hose your system; you need to resize
> the physical volume (PV).  You might be able to do this by doing a
> resize2fs/lvreduce, making sure that no physical extents (PEs) are in
> use above some offset (probably the case if it was a linear contiguous
> allocation), do a vgcfgbackup of the LVM2 metadata (which is in text form;
> hooray!), hack it to reduce the extent counts, and then do a vgcfgrestore.

Gotcha. Hopefully once the filesystem is resized down and the lvreduce
is done, moving the physical partition boundary will not destroy any
allocated PEs, good call on the vgcfgbackup/restore. I wouldn't know
where to start working out the new PE count for the restore though...
Will vgdisplay show me the new PE count after the resize?

> Alternatively (and "more safely"), you could plug in a USB2 drive, and do a
> pvmove/vgreduce/pvremove/fdisk/pvcreate/vgextend/pvmove. [I say "more safely"
> in scare quotes, because using usb-storage for multi-gigabyte copies
> can cause problems on lots of lousy USB hardware.]

I have a 40Gb USB2 disk which works well on this box, so maybe I'll
consider at least mirroring to that first, in case everything goes runny.

> Finally, it might just be easier to do a full backup and restore, especially
> if your laptop has a GigE interface.

Maybe. It's certainly possible as a last resort if everything screws up
or is going to take more than a couple of hours.

> If this is only for experimentation, perhaps you might consider installing
> Solaris 10 to run under Xen?  I believe there is a port to Xen domU.

Nope, permanent change, and this lappy only has 256Mb, so VM's are
pretty much out of the question.

You've been a great help, Bill. Thanks indeed!

Craig.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.1 (GNU/Linux)

iD8DBQFDegOnMDDagS2VwJ4RAgr5AKCgPFG0P4gkmO8G1PZD5Naju6jqNgCfR+ee
DOTsKQfymWWcPlkDG6IT+Qs=
=EOn3
-----END PGP SIGNATURE-----