Shell Programming and Scripting

Hi,

I have a main script which will login to different machines one by one and execute the another script as input which will execute some commands after login to the machine. i used while loop and it executes it like ssh to a machine and running the sub script, then moving to the second machines and so on. it is a kind of series activity.

but i want it to do it parellely, then what should i do. please suggest.
i tried to put "&" at the end of while loop so it will start the sub script in each machine at the back end. but it is not working as expected.

my main script code piece is something like,

Code:

while read machine
do
export machine=`echo $machine`
ssh $USER@$machine < $STEPS > $machine_$PRI.log
done < $MACHINE &

Code:

while read machine; do
  ssh "$USER@$machine" < "$STEPS" > "$machine_$PRI.log" &
done < "$MACHINE"