Shell Programming and Scripting

hi !

i have generated a RSA key successfully.

But wen i execute the script the " df -k;hostname" is displayed
only for the first device in the ip.txt.

i have several devices in the ip.txt 1 ip a line . . . i wanna ssh each ip
in the ip.txt n execute "df -k;hostname"


wast the problem in this script ?????

#!/bin/ksh
while read line_by_line
do
echo ${line_by_line}
ssh ${line_by_line} “df -k;hostname”
done < ip.txt