home | list info | list archive | date index | thread index

Re: [OCLUG-Tech] Need some advice re: RAID and LVM ?!?

Bryan Larsen wrote:
: > 1) I know I'll be doing something different, and I don't know how much disk
: > to allocation to Partition N for Program X.  LVM allows me to leave
: > unpartitioned space on the drive, and dynamically allocate it as needed.
: > (Note that this is a fairly mild benefit, save in corner cases.)
: The benefit is not so mild when you add a new disk to your system -- you 
: can add it to the group and expand a partition beyond the single disk.

The same benefit can be achieved by creating a filesystem on the new drive,
and just mounting it somewhere in the FS tree.  It's a bit trickier to get
going, but has exactly the same benefit, with none of the drawback.  Note
that this drawback is exactly the same as implementing a striped RAID array,
which, as you pointed out, makes this approach less than ideal.

Okay, so it's not the /exact/ same benefit, and it does require a certain
amount of effort, meaning LVM is much easier to do.  But personally, due to
that nasty striped array drawback, I avoid this whenever possible.