RAID support...
To whom it may concern,
Not that this is a show stopper, but it seems that the LVM is missing important capabilities such as RAID 1 & 5. I see that you already support RAID 0, but that's it. In my opinion, it makes sense to merge the RAID support (seperate product) with the LVM product. Because the two really complement each other.
Sincerely,
Michael O'Rourke
Unix System Admin
Per-Se' Technologies
Quoted 7 lines · Michael O'Rourke
To whom it may concern,
Not that this is a show stopper, but it seems that the LVM is missing important capabilities such as RAID 1 & 5. I see that you already support RAID 0, but that's it. In my opinion, it makes sense to merge the RAID support (seperate product) with the LVM product. Because the two really complement each other.
I think the two problems are completely orthogontal and
complement eachother in much the same way as applications complement an OS. I question whether even RAID0 support is really necessary in LVM. RAID should be stacked below, or above LVM, not packed inside.
Have fun (if at all possible),
Signature · 4 lines
"It does me no injury for my neighbor to say there are twenty gods or no God. It neither picks my pocket nor breaks my leg." --- Thomas Jefferson "Go to Heaven for the climate, Hell for the company." -- Mark Twain -- Eric Hopper ([email protected] http://www.omnifarious.org/~hopper) --
Michael,
I am replying to you personally, and not forwarding it to the list, not
sure if that is correct netiquetee or not. Here is the a link to the FAQ entry that discuss precisely the issue. Basically, the primary developer disagrees with you.
I happen to agree with him, but that is because I end up using software RAID and mirror everything and then build LVM devices out of them. Technically there is not speed advantage for doing it for anything except for RAID0 in the LVM. It causes a lot of code duplication between the software RAID and the LVM.
A strong case could be made for a more GUI/command line capable disk
volume management that encompassed RAID/LVM/GFS/ext3/XFS/JFS/ReiserFS/nb and every other thing under the sun to make administration easier, but well, somebody will get to it, just not today.
Kirby
Quoted 14 lines · Michael O'Rourke
To whom it may concern,
Not that this is a show stopper, but it seems that the LVM is missing important capabilities such as RAID 1 & 5. I see that you already support RAID 0, but that's it. In my opinion, it makes sense to merge the RAID support (seperate product) with the LVM product. Because the two really complement each other. Sincerely, Michael O'Rourke
Unix System Admin
Per-Se' Technologies_______________________________________________
linux-lvm mailing list
[email protected]
http://lists.sistina.com/mailman/listinfo/linux-lvm
read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html
Signature · 1 line
Real Programmers view electronic multimedia files with a hex editor.
Quoted 2 lines · Eric M. Hopper
OS. I question whether even RAID0 support is really necessary in LVM. RAID should be stacked below, or above LVM, not packed inside.
Totally agreed. There is working RAID0 code in the Software-RAID. Why blowing up the kernel with two RAID0-code-trees...
Maybe one could 'migrate it out' - mark it as deprecated, deny to create, but support old ones still a lot of time - something like this.
regards,
Mario
-- Mario 'BitKoenig' Holbe <[email protected]> on 12/29/01 11:42:44 +0100
Quoted 6 lines · Eric M. Hopper
Quoted 2 lines
OS. I question whether even RAID0 support is really necessary in LVM. RAID should be stacked below, or above LVM, not packed inside.
Totally agreed. There is working RAID0 code in the Software-RAID. Why blowing up the kernel with two RAID0-code-trees...
There really isn't any "RAID" anything code in LVM. The striping, etc, capacity that combines PV's isn't about RAID since it works above the hardware level. RAID0 knows low-level things about the disk drives as hardware; LVM only knows about PV's, which are a software abstracton of hardware.
As an example, if you used a RAID controller to combine two drives you'd be stuck with both drives as RAID0 for all time. No striping, whatever, just appending the space. With LVM you can stripe some LV's, have others on one or the other disk and other's growing.
I've never seen a working case of RAID(n>0) being useful on LVM. The main reason is that RAID[135+] are about increasing hardware reliability while LVM is about abstracting hardware out of existance. Stacking LVM on top of RAID gives the best of both: Increased flexability of the large spaces on combined disks that are more reliable together.
--
Steven Lembark 2930 W. Palmer
Workhorse Computing Chicago, IL 60647
+1 800 762 1582