ZFS - RAIDZ1 Recovery (Evgeny Sam)

[Michelle Sullivan]

Kevin P. Neal wrote:
> On Sun, May 29, 2016 at 07:31:29AM -0700, Evgeny Sam wrote:
>> I clonned the drives as follows:
>>       1. Created bit-to-bit images with R-Studio (I was hoping to use it to
>> restore the data)
>>       2. Restored the images to the new drives
> A quick check of their web site shows zero support for ZFS.
>
> There are several good ways to duplicate a disk, and at the top of the
> list are tools known to the people you are going to need help from. That
> means using the 'dd' command to duplicate the entire disk including the
> GPT labels. Or use something from Polytropon's list posted to these lists
> (usually the questions list mostly) every so often.
>
> The dd command when given the "conv=noerror,sync" option can be used to
> duplicate an entire disk. Then a ZFS scrub can correct the lost blocks.

<records those switches for future reference>

You know it has occurred to me on more than one occasion that having a 
disk added for online replacement of a failed disk, and using zfs 
replace, it's surprising that internal to zfs it doesn't try exactly 
that... bit/sector copy the drive from the old to the new replacement 
before switching to a scrub... if it did it would, on my system, cut the 
resilver time from 10 days to however long it takes for 3T of data to 
copy (likely <24hrs).
>
> Does R-Studio copy the entire disk including GPT specific parts, or does
> it copy partitions of disks? It isn't obvious which one it does from your
> description.
>
It does both (either) - depending on how you start it.  The lack of 
support for zfs is a lack of being able to read and recover the contents 
of a zfs disk... nothing more nothing less.  (I have R-Studio here and 
have used it in anger many times.)

-- 
Michelle Sullivan
http://www.mhix.org/