Add ssh key and some fixes for constant password asking on remote end

zfs-move-over-ssh.sh

@@ -17,13 +17,14 @@ Arguments:
 
 Options:
   -n, --dry-run              Print the ZFS and SSH commands without running them.
-  -i, --identity-file FILE   SSH private key to use.
+    -i, --identity-file FILE   SSH private key to use.
   -p, --ssh-port PORT        SSH port to use.
   --destroy-source-snapshots Destroy each local migration snapshot after its successful receive.
   -h, --help                 Show this help.
 
-The remote SSH account must be able to run `sudo -n zfs receive` without a
-password prompt. This script does not destroy source filesystems or data.
+SSH must use key or agent authentication; password prompts are disabled. The
+remote SSH account must be able to run `sudo -n zfs receive` without a password
+prompt. This script does not destroy source filesystems or data.
 EOF
 }
 
@@ -34,7 +35,7 @@ die() {
 
 DRY_RUN=false
 DESTROY_SOURCE_SNAPSHOTS=false
-SSH_OPTIONS=()
+SSH_OPTIONS=(-o BatchMode=yes)
 
 while (($#)); do
     case "$1" in
@@ -89,7 +90,7 @@ zpool list -H -o name "$SOURCE_POOL" >/dev/null || die "source pool does not exi
 
 if ! $DRY_RUN; then
     ssh "${SSH_OPTIONS[@]}" "$REMOTE_HOST" 'sudo -n zfs list -H -o name -t filesystem >/dev/null' \
-        || die "cannot run 'sudo -n zfs' on $REMOTE_HOST"
+    || die "cannot connect with non-interactive SSH or run 'sudo -n zfs' on $REMOTE_HOST"
 fi
 
 map_destination() {