Zfs error after native MP was activated previously under powerpath (EMC) Control.

root@noc-netbackupM # zpool status -x

  pool: nb_new

state: UNAVAIL

status: One or more devices could not be opened.  There are insufficient

        replicas for the pool to continue functioning.

action: Attach the missing device and online it using 'zpool online'.

   see: http://www.sun.com/msg/ZFS-8000-3C

scan: none requested

config:

        NAME          STATE     READ WRITE CKSUM

        nb_new        UNAVAIL      0     0     0  insufficient replicas

          emcpower0a  UNAVAIL      0     0     0  cannot open

This error after native MP was activated previously under powerpath (EMC) Control.