Disk Utility RAID hates me -- two external drives

[Zakster82]

Hi all,

I recently bought two identical 3TB Seagate USB drives. I have them connected to my Mac Mini and I want to set them up on RAID mirroring for my iTunes library. This is solely for the purposes of protection against a failed disk--I know the caveats regarding mirroring vs backup.

However every time I try to create the array in Disk Utility, I get "POSIX reports: the operation couldn't be completed. Operation not permitted." Any ideas, or at least advice where I can get more diagnostic information?

Thanks!

 

[ksbarnz]

Hi, did you figure out a solution to the problem? I am having the same problem with the exact same drives. I am about to re-format them and write the drives with zeros but that will take over 20 hours per drive.

 

[j3r3my]

Same problem - cannot find an answer

I've the same problem - and cannot find an answer.
Forums, Seagate etc
So my question is - what drives can anyone recommend to build a big, safe RAID0 array with?