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SSH session doesn't terminate and give the tty back when executed inside a here document. Below is the code snippet that's inside my shell script:

ssh -t -t root@$HOST_ADDRESS <<TERM_STRING
cd /tmp/
sleep 2
exit 0
TERM_STRING

After the command exit 0, the terminal is stuck and doesn't give me the tty back. Is there something I am doing wrong?

This is what I get after trying the SSH with -v flag

[root ~]# ssh -v -t -t 10.215.194.38
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 10.215.194.38 [10.215.194.38] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/id_rsa type 1
debug1: identity file /root/.ssh/id_dsa type -1
debug1: loaded 3 keys
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.2
debug1: match: OpenSSH_5.2 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-cbc hmac-md5 none
debug1: kex: client->server aes128-cbc hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host '10.215.194.38' is known and matches the RSA host key.
debug1: Found key in /root/.ssh/known_hosts:5
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received

debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Next authentication method: gssapi-with-mic
debug1: Unspecified GSS failure.  Minor code may provide more information
Unknown code krb5 195

debug1: Unspecified GSS failure.  Minor code may provide more information
Unknown code krb5 195

debug1: Unspecified GSS failure.  Minor code may provide more information
Unknown code krb5 195

debug1: Next authentication method: publickey
debug1: Trying private key: /root/.ssh/identity
debug1: Offering public key: /root/.ssh/id_rsa
debug1: Server accepts key: pkalg ssh-rsa blen 277
debug1: read PEM private key done: type RSA
debug1: Authentication succeeded (publickey).
debug1: channel 0: new [client-session]
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LANG = en_US

Last login: Wed Jan 23 14:02:39 2013 from 10.134.232.195
[root@10.215.194.38 ~]# exit 0

The only thing that stands out for me is the line:

debug1: Next authentication method: gssapi-with-mic
debug1: Unspecified GSS failure.  Minor code may provide more information
Unknown code krb5 195
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try pressing <enter>~. (mind the ., it belongs!) –  guntbert Jan 23 '13 at 21:13
    
Yeah, got that solution earlier from another forum. But, unfortunately I have this SSH session running inside a shell script....Unless someone can show me a way to pass Enter ~ . inside the script :-P –  user2001669 Jan 23 '13 at 21:22

1 Answer 1

What do you want to do exactly?

To execute multiple remote commands you can simply do this:

ssh root@$HOST_ADDRESS "<command> ; <command> ; etc ..."

The "here document" is feeded to standard input of the remote process, so you may do it this way if you wish (note that you need to specify a shell, like /bin/sh here, as remote command):

ssh root@$HOST_ADDRESS /bin/sh <<TERM_STRING
cd /tmp/
sleep 2
exit 0
TERM_STRING

the "-t" switch is needed only if one of the remote commands have to interact with the local tty, for exemple when using "vi":

ssh -t root@$HOST_ADDRESS vi file
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