Raid or LVM

[Kevin Wang]

On Mon, 11 Oct 2004 07:55:15 -0500, Will McCorkle
<wmccorkle at dgsystems.com> wrote:
> I have been working on a project and have come to wall. I need something
> that will allow more than 256mg in a file size and still allow me to add or
> remove disks and space at any time. LVM2 only allows 256mg as far as the
> documents say and raid seems to be a one shot option (set up disk(s) create
> file system, done). Does any one have a suggestion for this problem? 

If you really need hot plug, then you need to go to a external raid
solution.  It's not going to be cheap.  the biggest issue with hot
plug is having the right hardware support.  scsi is probably the best
supported for hotplug, though sata was designed with this in mind. 
the problem is that when you plug and unplug anything, you get noise
on the bus, and other drives can get corrupted data, or at least some
interruption in service.  they require special hardware to isolate
each drive from each other to prevent these electrical hardware
problems.

google for "linux external raid", and probably the type of unit you'd
look at would be a scsi attached raid of ide disks.  smaller units fit
4 of 5 disks into one enclosure.

be sure to verify that the raid is supported under linux. you need to
be able to monitor the status of the raid to know when it's running in
degraded mode.

   - Kevin