Recover ZFS volume with parity CRC errors

I would like to know how I can get a 5 disk FreeNAS ZFS volume recovered, my server has a raid card with individual drives presented no hardware raid, the FreNAS system created a ZFS volume using the 5 drives like a RAID 5 with parity.
After the card failed I replaced it and I now have a parity CRC error so FreeNAS cant import the volume, is there any way to force mount even with the CRC error?
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It really depends on what the controller did.  If it crunched on the drives for more than a second (or worst case at least an hour), then it but RAID parity information on top of the drives.  If that is the case, and you had anything less than a RAIDZ2 then the data is gone forever.

Even if it had a RAIDZ2 and the controller did a resilvering to give you a RAID5 then you're going to need somebody like  They'll charge you a minimum of $5K to get this back, but could cost tens of thousands of dollars.
atorexAuthor Commented:
you may be correct I dont know what the actual issue is, when I do a zpool status this is what I get

[root@NAS2] /# zpool status
  pool: ZFS02
 state: ONLINE
status: Some supported features are not enabled on the pool. The pool can
      still be used, but some features are unavailable.
action: Enable all features using 'zpool upgrade'. Once this is done,
      the pool may no longer be accessible by software that does not support
      the features. See zpool-features(7) for details.
  scan: scrub repaired 0 in 12h19m with 0 errors on Sun May 24 12:19:13 2015

      NAME                                            STATE     READ WRITE CKSUM
      ZFS02                                           ONLINE       0     0     0
        raidz2-0                                      ONLINE       0     0     0
          gptid/9bce7e30-bdb9-11e3-8f40-000e0ce5a0b3  ONLINE       0     0     0
          gptid/9c688a3b-bdb9-11e3-8f40-000e0ce5a0b3  ONLINE       0     0     0
          gptid/9d0222ac-bdb9-11e3-8f40-000e0ce5a0b3  ONLINE       0     0     0
          gptid/9d9d9497-bdb9-11e3-8f40-000e0ce5a0b3  ONLINE       0     0     0
          gptid/9e4e8399-bdb9-11e3-8f40-000e0ce5a0b3  ONLINE       0     0     0

errors: No known data errors

  pool: freenas-boot
 state: ONLINE
  scan: none requested

      freenas-boot  ONLINE       0     0     0
        ada6p2    ONLINE       0     0     0
Davis McCarnOwnerCommented:
I have recovered this type of failure before, more than once!
What I would do is:
Setup a working windows PC with readily accessible secondary and tertiary drive connections and install the trial version of 's pro utility.
Mark each drives position in the RAID (!!!) so you can put them back.
One at a time, connect a drive to the PC and check it with HDTune.  Look on the Health tab and inspect the Data column for (05) Reallocated Sector Count, (C4) Reallocated Event Count, and (C5) Current Pending Sector.  If any of them are not 0 (zero), that drive is failing (period).  If you want to be completely thorough, run the error scan which can be time consuming; but, even one red box means further action is needed.
I use WinHex; but, Rawcopy is a free utility which will do sector copies of drives which you find are failing:
Get enough replacement drives to copy the failing ones to (preferably like sized if not identical; but, be very careful to KNOW which drive is which!) and clone/copy the failing drive(s) to replacements.
Put all of the drives back in the array with the copies replacing the originals.
Pray a little and fire things up.

The only time I had conniption fits was with an array wherein their IT weenie had tried to redefine the array, fouling up the signatures which required a complete set of replacements so I could adjust the volumes to match the original partition structure and then copying those sectors back to the recovery set.  It was; however, the records for a 50 doctor practice!

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