On 21/12/22 14:19, Frank Steinmetzger wrote:
Am Wed, Dec 21, 2022 at 05:53:03AM +0000 schrieb Wols Lists:
On 21/12/2022 02:47, Dale wrote:
...
In layman’s term, a stripe of mirrors. Raid-1 is the mirror, Raid-0 a (JBOD)
pool. So mirror + pool = mirrorpool, hence the 1+0 → 10.
...
I tend to use older drives that have led a hard life - so failure
happens and I have to be prepared for it (by having good backups!)
I have found mirrors to be problematic - sometimes when one drive
fails, it causes a cascade of fails that includes the data on the
mirror. With raid-10, its worse (even more fragile). When I eventually
moved away from raid for my main data store it was because of a
catastrophic failure of a bcache ssd fronting one of the mirrors causing
all data to be lost - somewhat self-caused by using bcache to try and
get some more speed out of the system, but as a RAID 10 with 4 HDD
fronted by 4x SSD it should have survived ... In the end, I realised
that raided data gave me a small speedup with little or no benefit as
regards reliable data storage. I currently have one linux raid 10 using
4xSSD's that has suffered one SSD abrupt failure and survived - which I
regard as "being lucky". SSD's are an issue as they usually fail
abruptly without warning whereas spinning rust usually gives some warning.
I've never tried RAID-6 as it was still considered buggy/risky at the time.
No matter what storage system you use, offline backups are better - raid
is NOT a viable backup.
Fun, innit?
YEP!
BillK
