RAID config

[MattRVBC]

RAID 5 was purely an example of disk striping that I'm familiar with and was using this to compare the advantages with RAID6. Apologies for any inconvenience, this didn't obviously read as I hoped.

[Gaz]

Thank you everyone for your input, I must say it was funny to see this thread turn into people being very defensive about their own RAID choices.

 

I went with RAID10 with a spare that will kick in when it detects a predicted failure. The only disadvantage to RAID10 over RAID 5 is the cost, they have the exact same drive failure protection in that they can only suffer 1 drive failure.

 

Thanks again guys.

[Bobby_Tables]

Thank you everyone for your input, I must say it was funny to see this thread turn into people being very defensive about their own RAID choices.

 

I went with RAID10 with a spare that will kick in when it detects a predicted failure. The only disadvantage to RAID10 over RAID 5 is the cost, they have the exact same drive failure protection in that they can only suffer 1 drive failure.

 

Thanks again guys.

 

Actually, RAID10 can suffer multiple drive failures - as long as not all of the failed drives come from the same mirror set. If you have a four drive RAID10, for example, one drive from each mirrored pair can fail without the array going offline; you are effectively left with a RAID 0 until you can replace the problem drives and rebuild the mirrors.

[pcstru]

I went with RAID10 with a spare that will kick in when it detects a predicted failure. The only disadvantage to RAID10 over RAID 5 is the cost, they have the exact same drive failure protection in that they can only suffer 1 drive failure.

There are other some other significant advantages - the performance while degraded and during a rebuild is much better, which means the window during which you are vulnerable to a second failure in the same mirror set is smaller.

[tmcd35]

There are other some other significant advantages - the performance while degraded and during a rebuild is much better, which means the window during which you are vulnerable to a second failure in the same mirror set is smaller.

 

Which is why decisions such as this should be taken after a careful cost:benefit analysis, rather than a technicians whim or flavour of the month technology reasons. Ultimately only @Gaz can say what is right in his particular circumstances. To my mind having a ratio of 3 drives redundant, 2 drives live, leads to questions like why 600Gb drives where used instead of 300Gb drives? But that's based on experience of supporting local primary schools not experience of @Gaz's particular setup.