David Hart wrote:
On Sun, 2005-10-02 at 16:32 +0900, Craig Hagerman wrote:
Good info Eric. Thanks. What if you have already installed Ubuntu
WITHOUT LVM, and later want it. Is is possible to changr oe things after
an install?
Yes it's possible but depends on how you have your hard disk partitioned
currently.
You need enough spare space to create an initial LVM partition so that
you can copy a current partition into a logical volume created in the
LVM. As you free up your current partitions you can add them to the LVM
'pool'.
this is a great example of where the poor man's LVM comes in handy. You
shrink down your root and boot partitionsto something reasonably small,
remembering of course to leave sufficient space for updates and growth.
Then you take the remaining space which should be "free" and install LVM
I would strongly recommend that you do this from a boot/live CD to
ensure clean copies.
Also be very sure you have read the LVM docs carefully before trying to
put your '/' partition in LVM; it needs special treatment as the
bootloader can't read LVM volumes. I myself never bother with '/' in
LVM; if I need to set a machine to multi-boot I simply put a few small
normal '/' partitions at the beginning of the hard disk.
this is a very good point that David raises. Playing with breezy I
discovered that it will support root under LVM quite nicely and
automatically creates a boot partition of a reasonable size. I would
trust this (mostly) for production but, but, but don't try this trick by
yourself without a lot of experience. Leave root out of LVM if you are
converting post install. Unless of course you are looking to experience
a royally screwed up system and reinstalling so the breezy installer can
do things right the next time.
Be aware, though, that if you spread your system across two disks you'll
have approximately doubled the chance of your system becoming hosed due
to disk failure.
Craig, here's a question you should also ask yourself. What's your
disaster recovery plan? how are you going to recover if one of the
discs in the LVM set goes out to lunch. Here's one suggestion. Shrink
root as I suggested above. make a partition on the second disc the same
size as the recently freed disk space on the first. Then use raid one
mirroring with LVM on top of the raid. data redundancy and LVM to play
with. Then you can use the remaining space on the second disc for
something. Not sure what but something relatively useless like /var/log
or /mymusic. :-)
in theory you should be able to make both discs fully raid but raid and
root are even more problematic than raid and LVM.
--- eric
--
ubuntu-users mailing list
ubuntu-users@xxxxxxxxxxxxxxxx
http://lists.ubuntu.com/mailman/listinfo/ubuntu-users
|