need help to design screen fail-over

[J. Bakshi]

Hello list,

I am using expect command to do auto ssh login. It is working well with
screen like

` ` `
spawn ssh  '$ssh_Server'  -t  "screen -aUS  '$ssh_Server'  -dR bash -l"
expect "*assword:"
send '$PASSWORD'
send "\r"
interact'
` ` `
All OK.

Now I am trying to do a screen fail over, so that if the remote server
does not have screen then it will do just ssh login. I have tried with

` ` `
spawn ssh " '$ssh_Server' -t  screen -aUS  '$ssh_Server' -dR bash -l ||
'$ssh_Server' "
` ` `

and it reports error as

` ` `
send: spawn id exp4 not open
    while executing
"send testpassword"
` ` `

What might be wrong here ? Any clue ?
Thanks

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