Which method would you use to modify the ZFS shadow migration daemon defaults to increase the concurrency and overall speed of migration?

You created a new zpool. Now you need to migrate the existing ZFS file system from pool1/prod to
pool2/prod.
You have these requirements:
1. Users must have access to the data during the migration, so you cannot shutdown the file
system while the migration takes place.
2. Because you want to copy the data as quickly as possible, you need to increase the server
resources devoted to the ZFS migration.
Which method would you use to modify the ZFS shadow migration daemon defaults to increase
the concurrency and overall speed of migration?

A.
Svccfg – s filesystem/shadowd:default
setprop config_params/shadow_threads=integer: 16
end
svcadm refresh filesystem/shadowd: default

B.
Specify the -b <blocksize> option with the zfs create command and increase the value of
<blocksize>

C.
Use the -o -volblocksize=<blocksize>option with the zfs create command and increase the
value of the default <blocksize>.

D.
Svccfg -s filesystem/zfs: default
setprop config_params/shadow_threads = integer: 16
end
svcadm refresh filesystem/zfs:default

Explanation:
shadowd is a daemon that provides background worker threads to migrate data for
a shadow migration. A shadow migration gradually moves data from a source file system into a
new “shadow” file system. Users can access and change their data within the shadow file system
while migration is occurring.
The shadowd service is managed by the service management facility, smf(5). Administrative

actions on this service, such as enabling, disabling, or requesting restart, can be performed using
svcadm(1M). The service’s status can be queried using the svcs(1) command.
The svccfg(1M) command can be used to manage the following parameter related to shadowd:
config_params/shadow_threads
Note: Oracle Solaris 11: In this release, you can migrate data from an old file system to a new file
system while simultaneously allowing access and modification of the new file system during the
migration process.
Setting the shadow property on a new ZFS file system triggers the migration of the older data. The
shadow property can be set to migrate data from the local system or a remote system with either
of the following values:
file:///path
nfs://host:path
Reference: man shadowd