| 1 |
On Samstag 02 Mai 2009, Anthony Metcalf wrote: |
| 2 |
> Jim Cunning wrote: |
| 3 |
> > On Saturday 02 May 2009 13:43:27 Volker Armin Hemmann wrote: |
| 4 |
> >> how do you do 10 with only two disks? You need four! |
| 5 |
> >> the kernel is able to autoassemble - so you don't need an initrd - me I |
| 6 |
> >> hate initrds. |
| 7 |
> > |
| 8 |
> > RAID10 = RAID1+0. It works fine with 2 disks. I was able to create it |
| 9 |
> > first with one drive missing and then add the second, which sync'ed |
| 10 |
> > without problems. |
| 11 |
> |
| 12 |
> Theoretically, for RAID 10, you need 4 disks, two raid 1's then used to |
| 13 |
> make a RAID 0 (or the other way round, I forget....) |
| 14 |
> |
| 15 |
> BUT, mdadm will use partitions instead of disks.....So you can make a |
| 16 |
> RAID 10 where each stripe takes up half the disk, and the stripes are |
| 17 |
> mirrored on each disk....Or each disk is mirrored on itself, and the two |
| 18 |
> disks stripped....Or something.... |
| 19 |
> |
| 20 |
> Won't give you the performance advantages of RAID 10 though, but will |
| 21 |
> still waste half your space..... |
| 22 |
|
| 23 |
even worse - performance will be even more reduced because the harddisk not |
| 24 |
only have to write the own stripe but the mirrored one too. Results in more |
| 25 |
seeking. Seeking = bad. |
| 26 |
|
| 27 |
Simple Raid1 would be a lot better. And since Raid1 is 'striping' the read |
| 28 |
accesses two you have a nice little improvement there. |
Archives