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I have this code :

HOSTS="host1 host2"
    For hostname in ${HOST} ;
do ssh -tt ${USERNAME}@${hostname} << EOF
HOSTSN="test"
echo ${HOSTSN}
exit
EOF
Done 

The variable HOSTSN is empty, can you tell me why?

I have this code :

HOSTS="host1 host2"
    For hostname in ${HOSTS} ;
do ssh -tt ${USERNAME}@${hostname} << EOF
HOSTSN="test"
echo ${HOSTSN}
exit
EOF
Done 

The variable HOSTSN is empty, can you tell me why?

I have this code :

HOSTS="host1 host2"
    For hostname in ${HOST} ;
do ssh -tt ${USERNAME}@${hostname} << EOF
HOSTSN="test"
echo ${HOSTSN}
exit
EOF
Done 

The variable HOSTSN is empty  , can you tell me why  ?

I have this code :

HOSTS="host1 host2"
    For hostname in ${HOST} ;
do ssh -tt ${USERNAME}@${hostname} << EOF
HOSTSN="test"
echo ${HOSTSN}
exit
EOF
Done 

The variable HOSTSN is empty, can you tell me why?