[NTLUG:Discuss] Using SATA Drives to Replace Tape

[Kevin Brannen]

Robert Pearson wrote:

> ...
>
>Quote from the article---
>"The duty cycle - when the disks are spinning - of Serial ATA drives
>is between 25% and 50%. The products from the other companies Taylor
>was looking at spun their Serial ATA disks 100% of the time, meaning
>that there would be more frequent drive failures."
>
>--- this sort of threw me. For rapid query response the disks need to
>be spinning. Staggered spin-up is probably the order of the day in these
>"giant" disk arrays. Anybody know? Selective spin-up is even better but
>I don't know anyone who knows the Content, or has it mapped, well
>enough to spin-up selectively. Unless Copan and MAID provide this.
>  
>
...

I believe you misuderstood how he was using all this.  The MAID was to 
replace his tape backups (note he said it was his Tier 4 data array).  
He also described it as "write once use almost never".  So he only 
"queries" from it upon failure in his Tier 1 or 2 arrays when he would 
have to rebuild them.

Kevin