During my talk, I spoke briefly about upgrading one of my machines from 3TB disks to 4TB disks.
Here's a "zfs status" output (obviously with some critical details scrubbed)

This is a raid 60 (4, 8 disk raid 6's).  I'm replacing 4 disks, one from each of the strip sets.  What I captured this output I'd just put in the fourth disk.  So that 252h is now down to 15h, and likely soon it'll be even lower.  Obviously, I/O load on the subsystem will cause this to stretch out. Note the "New Disk" labels were added for emphasis.

bash-4.2# zpool status XXXXXX
  pool: XXXXXXX
 state: DEGRADED
status: One or more devices is currently being resilvered.  The pool will
        continue to function, possibly in a degraded state.
action: Wait for the resilver to complete.
 scan: resilver in progress since Wed Jul  8 10:30:22 2015
    945M scanned out of 11.9T at 13.7M/s, 252h54m to go
    945M scanned out of 11.9T at 13.7M/s, 252h54m to go
    110M resilvered, 0.01% done
config:

        NAME                         STATE     READ WRITE CKSUM
        XXXXX                      DEGRADED     0     0     0
          raidz2-0                   DEGRADED     0     0     0
            c3t5000C500637AADD3d0    ONLINE       0     0     0
            replacing-1              DEGRADED     0     0     0
              c3t5000C50064E9441Fd0  FAULTED      1   166     0  too many errors
              c3t5000C500637875EBd0  ONLINE       0     0     0  (resilvering)           <---- New Disk
            c3t5000C5004DFE165Ad0    ONLINE       0     0     0
            c3t5000C5004E0F3A80d0    ONLINE       0     0     0
            c3t5000C5004E1B6EE1d0    ONLINE       0     0     0
            c3t5000C5004E23870Bd0    ONLINE       0     0     0
            c3t5000C5004E2AC08Fd0    ONLINE       0     0     0
            c3t5000C5004E2AE946d0    ONLINE       0     0     0
          raidz2-1                   DEGRADED     0     0     0
            c3t5000C500637879E7d0    ONLINE       0     0     0
            replacing-1              DEGRADED     0     0     0
              c3t5000C5004E2B1B22d0  FAULTED    139   222     0  too many errors
              c3t5000C500637ACF67d0  ONLINE       0     0     0  (resilvering)         <------ New Disk
            c3t5000C5004E2BE74Dd0    ONLINE       0     0     0
            c3t5000C5004E2BEA7Fd0    ONLINE       0     0     0
            c3t5000C5004E2C0B84d0    ONLINE       0     0     0
            c3t5000C5004E2C5397d0    ONLINE       0     0     0
            c3t5000C5004E2D0C39d0    ONLINE       0     0     0
            c3t5000C5004E2D1F13d0    ONLINE       0     0     0
          raidz2-2                   DEGRADED     0     0     0
            replacing-0              DEGRADED     0     0     0
              c3t5000C5004E2D48F6d0  UNAVAIL      0     4     0  cannot open
              c3t5000C500637933B3d0  ONLINE       0     0     0  (resilvering) <----- New Disk
            c3t5000C5004E2D58DAd0    ONLINE       0     0     0
            c3t5000C5004E2D0821d0    ONLINE       0     0     0
            c3t5000C5004E2D3220d0    ONLINE       0     0     0
            c3t5000C5004E2D3749d0    ONLINE       0     0     0
            c3t5000C5006A581C22d0    ONLINE       0     0     0
            c3t5000C5004E25DFFFd0    ONLINE       0     0     0
            c3t5000C5004E129273d0    ONLINE       0     0     0
          raidz2-3                   DEGRADED     0     0     0
            replacing-0              DEGRADED     0     0     0
              c3t5000C5006A582FE8d0  FAULTED    146   130     0  too many errors
              c3t5000C50063747E77d0  ONLINE       0     0     0  (resilvering)  <----- New Disk
            c3t5000C50064D9AB36d0    ONLINE       0     0     0
            c3t5000C50064D98E37d0    ONLINE       0     0     0
            c3t5000C50064DF7F04d0    ONLINE       0     0     0
            c3t5000C50064DFAE39d0    ONLINE       0     0     0
            c3t5000C50064E3CBE0d0    ONLINE       0     0     0
            c3t5000C50064E401FEd0    ONLINE       0     0     0
            c3t5000C5004DE878BAd0    ONLINE       0     0     0

errors: No known data errors
bash-4.2# 

Thanks,
Tim.
--
I am leery of the allegiances of any politician who refers to their constituents as "consumers".