On 2017-03-26 12:14, Michael Neumann wrote:
1) On my main PC I'm planning to install DragonFlyBSD on a small SSD and
use two 6TB disks for my home directory: one disk for the master PFS,
one as a copy with HAMMER's mirror feature.
I have a 7200 rpm Seagate IronWolf and a 5400 rpm Western Digital Red.
Can I use them together or HAMMER's mirror feature requires (or work
best with) identical disks (or disks from different brands but same
speed)? If I can use them do you suggest using the faster disk for the
master or the mirror?
No problem here. You can even mirror over slow internet connections.
HAMMER is using logical mirroring, i.e. it creates two completely
separate file systems (with identical logical content), so neither the
physical block size, nor the speed of the disk matters. Of course you
have to give the second slower disk enough time to keep track.
A related question:
Can the mirror copy be accessed/mounted as a separate filesystem and if
so, can every file be read file-by-file or can it only be restored as
the whole dataset ???
I belive that ZFS mirror-stream (or what it's called) can only be
restored as the whole shebang but I have never tried it myself.
Long time since I had DF installed on a computer, might mitigate this
today but I don't have enough HD's to try this mirroring thing by myself
right now.
