Hi
I agree; in my opinion, software raid will always be faster than hardware raid and the
most important advantage is, that the speed of the sw raid will increase with an cpu
upgrade.
Dietmar
>----- Urspr�ngliche Nachricht -----
>Absender: [EMAIL PROTECTED]
>Betreff: Re: Failure of device - Hard vs. Soft
>Empf�nger: Joao Rochate
>Kopie-Empf�nger: [EMAIL PROTECTED]
>Datum: 14. Jun 1999 09:17
>
> Joao Rochate <[EMAIL PROTECTED]> writes:
> > * If I have a software RAID enabled system and my server fails, I can move
> > all the disks to another server and use the same /etc/raidtab to get disks
> > working again.
>
> Yes. If you use current alpha snapshot code, persistent superblocks
> and array autodetection, you won't even need to care about the disk
> order, the system will figure it out.
>
> > * If I have a hardware RAID system and server fails (also the RAID
> > controler) can I just move the disks to another server with the same RAID
> > card model and have the system working back again?
>
> Should work, although a controller might have some settings stored in
> NVRAM instead of on the disks (would seem stupid to me, but..)
>
> > I'm trying to do this cheap near-HA solution working. The software RAID
> > takes too much time to rebuild a failed 40Gb RAID system, so I'm thinking
> > of moving to a HW solution.
>
> Wrong reason. Software RAID is faster. The system CPU probably is a
> Pentium II or better, with MMX instructions. It can perform the RAID-5
> parity construction at way above the speed of the disks, and probably
> if you have an Ultra2 controller or two UltraSCSI controllers, the
> SCSI bus bandwidth also exceeds the disk capacity. The resync is
> happening at media speed. There's no way a hardware solution could be
> faster than that, and low-end devices are very likely slower.
>
> --
> Osma Ahvenlampi
>
>
