Sftp does not work for particular user

Hi,

Sftp does not work for user "infra" but ssh works fine. SFTP also works for remaining users. SFTP verbose log is attached here. Please check and recommended.

With Best Regards,
Md. Abdullah-Al Kauser

OID @vm-oid.banglalinkgsm.com:/u02/infra/product/104/orcl$sftp -vvv infra@172.16.10.179
Connecting to 172.16.10.179...
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to 172.16.10.179 [172.16.10.179] port 22.
debug1: Connection established.
debug1: identity file /home/infra/.ssh/id_rsa type -1
debug1: identity file /home/infra/.ssh/id_dsa type -1
debug1: loaded 2 keys
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.3
debug2: fd 3 setting O_NONBLOCK
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_init: found hmac-md5
debug1: kex: server->client aes128-cbc hmac-md5 none
debug2: mac_init: found hmac-md5
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
debug2: dh_gen_key: priv key bits set: 139/256
debug2: bits set: 531/1024
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug3: check_host_in_hostfile: filename /home/infra/.ssh/known_hosts
debug3: check_host_in_hostfile: match line 2
debug1: Host '172.16.10.179' is known and matches the RSA host key.
debug1: Found key in /home/infra/.ssh/known_hosts:2
debug2: bits set: 522/1024
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/infra/.ssh/id_rsa ((nil))
debug2: key: /home/infra/.ssh/id_dsa ((nil))
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug3: start over, passed a different list publickey,gssapi-with-mic,password
debug3: preferred gssapi-with-mic,publickey,keyboard-interactive,password
debug3: authmethod_lookup gssapi-with-mic
debug3: remaining preferred: publickey,keyboard-interactive,password
debug3: authmethod_is_enabled gssapi-with-mic
debug1: Next authentication method: gssapi-with-mic
debug3: Trying to reverse map address 172.16.10.179.
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

debug2: we did not send a packet, disable method
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/infra/.ssh/id_rsa
debug3: no such identity: /home/infra/.ssh/id_rsa
debug1: Trying private key: /home/infra/.ssh/id_dsa
debug3: no such identity: /home/infra/.ssh/id_dsa
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
infra@172.16.10.179's password:
debug3: packet_send2: adding 64 (len 55 padlen 9 extra_pad 64)
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
debug2: fd 4 setting O_NONBLOCK
debug3: fd 5 is O_NONBLOCK
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Entering interactive session.
debug2: callback start
debug2: client_session2_setup: id 0
debug1: Sending environment.
debug3: Ignored env HOSTNAME
debug3: Ignored env SHELL
debug3: Ignored env TERM
debug3: Ignored env HISTSIZE
debug3: Ignored env TMPDIR
debug3: Ignored env KDE_NO_IPV6
debug3: Ignored env QTDIR
debug3: Ignored env OLDPWD
debug3: Ignored env QTINC
debug3: Ignored env USER
debug3: Ignored env LD_LIBRARY_PATH
debug3: Ignored env LS_COLORS
debug3: Ignored env ORACLE_SID
debug3: Ignored env ORACLE_BASE
debug3: Ignored env KDEDIR
debug3: Ignored env MAIL
debug3: Ignored env PATH
debug3: Ignored env INPUTRC
debug3: Ignored env PWD
debug1: Sending env LANG = en_US.UTF-8
debug2: channel 0: request env confirm 0
debug3: Ignored env KDE_IS_PRELINKED
debug3: Ignored env ORACLE_TERM
debug3: Ignored env PS1
debug3: Ignored env SSH_ASKPASS
debug3: Ignored env SHLVL
debug3: Ignored env HOME
debug3: Ignored env TMP
debug3: Ignored env LOGNAME
debug3: Ignored env QTLIB
debug3: Ignored env CVS_RSH
debug3: Ignored env CLASSPATH
debug3: Ignored env LESSOPEN
debug3: Ignored env ORACLE_HOME
debug3: Ignored env G_BROKEN_FILENAMES
debug3: Ignored env HISTFILE
debug3: Ignored env _
debug1: Sending subsystem: sftp
debug2: channel 0: request subsystem confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel 0: rcvd adjust 2097152
Received message too long 1313808468
debug2: channel 0: read<=0 rfd 4 len -1
debug2: channel 0: read failed
debug2: channel 0: close_read
debug2: channel 0: input open -> drain
debug2: channel 0: ibuf empty
debug2: channel 0: send eof
debug2: channel 0: input drain -> closed
OID @vm-oid.banglalinkgsm.com:/u02/infra/product/104/orcl$debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
debug3: channel 0: will not send data after close
debug2: channel 0: almost dead
debug2: channel 0: gc: notify user
debug2: channel 0: gc: user detached
debug2: channel 0: send close
debug2: channel 0: is dead
debug2: channel 0: garbage collecting
debug1: channel 0: free: client-session, nchannels 1
debug3: channel 0: status: The following connections are open:
  #0 client-session (t4 r0 i3/0 o3/0 fd -1/-1 cfd -1)

debug3: channel 0: close_fds r -1 w -1 e 6 c -1
debug1: fd 0 clearing O_NONBLOCK
debug3: fd 1 is not O_NONBLOCK
debug1: Transferred: stdin 0, stdout 0, stderr 0 bytes in 0.1 seconds
debug1: Bytes per second: stdin 0.0, stdout 0.0, stderr 0.0
debug1: Exit status 0

This appears to be an error related to public-private key pair configuration issues.

One suggestion we see often in forum and blog when this happens is to clear out (or move to a temp location) all your key pairs on both server and client, rebuild and reinstall.

Hi Neo,

But ssh works fine for this user....so i think it is not a keypair issue. Please suggest.

But you can easily login when you use a regular password and not password-less, right?

Also, do you remember how you created your ssh key-pairs?

Many people create these key pairs and bind the keys to the ports; and ssh and sftp ports are not the same.

Also, did you try scp? Does scp work OK?

Your connection on the ssh port seems fine:

And, despite unaccepted authentication attempts, like

( you might want to check your kerberos setup)

and

you finally seem to log in successfully after entering a password (did you enter a password?):

This might be the culprit

as after that the session close seems to start. Do you have a similar debug log for the successful ssh connections? Do you supply a password there as well?

1 Like

Regarding this ...

Look here...

OpenSSH FAQ 2.9

To put it simply, .bashrc and .bash_profile etc have to be silent or they interfere with the sftp / scp connection protocol.

(1. result in google).

3 Likes

Hey Rudi,

That makes sense, since SSH and SFTP both run over the same port 22, as I recall.

Good catch.

Hi Rudic,

Yes, we have put password. SSH verbose log attached herewith.

Hi Neo,

We've checked and found keypair was not generated in system.

OID @vm-oid.banglalinkgsm.com:/home/infra/.ssh$pwd
/home/infra/.ssh
OID @vm-oid.banglalinkgsm.com:/home/infra/.ssh$ll -a
total 12
drwx------  2 infra dba   4096 Apr 18 09:20 .
drwx------ 18 infra users 4096 Apr 18 09:55 ..
-rw-r--r--  1 infra dba    797 Apr 18 11:13 known_hosts
OID @vm-oid.banglalinkgsm.com:/u02/infra/product/104/orcl$ssh -vvv infra@172.16.10.179
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to 172.16.10.179 [172.16.10.179] port 22.
debug1: Connection established.
debug1: identity file /home/infra/.ssh/identity type -1
debug1: identity file /home/infra/.ssh/id_rsa type -1
debug1: identity file /home/infra/.ssh/id_dsa type -1
debug1: loaded 3 keys
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.3
debug2: fd 3 setting O_NONBLOCK
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_init: found hmac-md5
debug1: kex: server->client aes128-cbc hmac-md5 none
debug2: mac_init: found hmac-md5
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
debug2: dh_gen_key: priv key bits set: 126/256
debug2: bits set: 507/1024
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug3: check_host_in_hostfile: filename /home/infra/.ssh/known_hosts
debug3: check_host_in_hostfile: match line 2
debug1: Host '172.16.10.179' is known and matches the RSA host key.
debug1: Found key in /home/infra/.ssh/known_hosts:2
debug2: bits set: 480/1024
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/infra/.ssh/identity ((nil))
debug2: key: /home/infra/.ssh/id_rsa ((nil))
debug2: key: /home/infra/.ssh/id_dsa ((nil))
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug3: start over, passed a different list publickey,gssapi-with-mic,password
debug3: preferred gssapi-with-mic,publickey,keyboard-interactive,password
debug3: authmethod_lookup gssapi-with-mic
debug3: remaining preferred: publickey,keyboard-interactive,password
debug3: authmethod_is_enabled gssapi-with-mic
debug1: Next authentication method: gssapi-with-mic
debug3: Trying to reverse map address 172.16.10.179.
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

debug2: we did not send a packet, disable method
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/infra/.ssh/identity
debug3: no such identity: /home/infra/.ssh/identity
debug1: Trying private key: /home/infra/.ssh/id_rsa
debug3: no such identity: /home/infra/.ssh/id_rsa
debug1: Trying private key: /home/infra/.ssh/id_dsa
debug3: no such identity: /home/infra/.ssh/id_dsa
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
infra@172.16.10.179's password:
debug3: packet_send2: adding 64 (len 55 padlen 9 extra_pad 64)
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Entering interactive session.
debug2: callback start
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 0
debug3: tty_make_modes: ospeed 38400
debug3: tty_make_modes: ispeed 38400
debug3: tty_make_modes: 1 3
debug3: tty_make_modes: 2 28
debug3: tty_make_modes: 3 127
debug3: tty_make_modes: 4 21
debug3: tty_make_modes: 5 4
debug3: tty_make_modes: 6 0
debug3: tty_make_modes: 7 0
debug3: tty_make_modes: 8 17
debug3: tty_make_modes: 9 19
debug3: tty_make_modes: 10 26
debug3: tty_make_modes: 12 18
debug3: tty_make_modes: 13 23
debug3: tty_make_modes: 14 22
debug3: tty_make_modes: 18 15
debug3: tty_make_modes: 30 0
debug3: tty_make_modes: 31 0
debug3: tty_make_modes: 32 0
debug3: tty_make_modes: 33 0
debug3: tty_make_modes: 34 0
debug3: tty_make_modes: 35 0
debug3: tty_make_modes: 36 1
debug3: tty_make_modes: 37 0
debug3: tty_make_modes: 38 1
debug3: tty_make_modes: 39 0
debug3: tty_make_modes: 40 0
debug3: tty_make_modes: 41 0
debug3: tty_make_modes: 50 1
debug3: tty_make_modes: 51 1
debug3: tty_make_modes: 52 0
debug3: tty_make_modes: 53 1
debug3: tty_make_modes: 54 1
debug3: tty_make_modes: 55 1
debug3: tty_make_modes: 56 0
debug3: tty_make_modes: 57 0
debug3: tty_make_modes: 58 0
debug3: tty_make_modes: 59 1
debug3: tty_make_modes: 60 1
debug3: tty_make_modes: 61 1
debug3: tty_make_modes: 62 0
debug3: tty_make_modes: 70 1
debug3: tty_make_modes: 71 0
debug3: tty_make_modes: 72 1
debug3: tty_make_modes: 73 0
debug3: tty_make_modes: 74 0
debug3: tty_make_modes: 75 0
debug3: tty_make_modes: 90 1
debug3: tty_make_modes: 91 1
debug3: tty_make_modes: 92 0
debug3: tty_make_modes: 93 0
debug1: Sending environment.
debug3: Ignored env HOSTNAME
debug3: Ignored env SHELL
debug3: Ignored env TERM
debug3: Ignored env HISTSIZE
debug3: Ignored env TMPDIR
debug3: Ignored env KDE_NO_IPV6
debug3: Ignored env QTDIR
debug3: Ignored env OLDPWD
debug3: Ignored env QTINC
debug3: Ignored env USER
debug3: Ignored env LD_LIBRARY_PATH
debug3: Ignored env LS_COLORS
debug3: Ignored env ORACLE_SID
debug3: Ignored env ORACLE_BASE
debug3: Ignored env KDEDIR
debug3: Ignored env MAIL
debug3: Ignored env PATH
debug3: Ignored env INPUTRC
debug3: Ignored env PWD
debug1: Sending env LANG = en_US.UTF-8
debug2: channel 0: request env confirm 0
debug3: Ignored env KDE_IS_PRELINKED
debug3: Ignored env ORACLE_TERM
debug3: Ignored env PS1
debug3: Ignored env SSH_ASKPASS
debug3: Ignored env SHLVL
debug3: Ignored env HOME
debug3: Ignored env TMP
debug3: Ignored env LOGNAME
debug3: Ignored env QTLIB
debug3: Ignored env CVS_RSH
debug3: Ignored env CLASSPATH
debug3: Ignored env LESSOPEN
debug3: Ignored env ORACLE_HOME
debug3: Ignored env G_BROKEN_FILENAMES
debug3: Ignored env HISTFILE
debug3: Ignored env _
debug2: channel 0: request shell confirm 0
debug2: fd 3 setting TCP_NODELAY
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel 0: rcvd adjust 2097152
Last login: Thu Apr 18 11:39:16 2019 from vm-oid.banglalinkgsm.com
NO TIMEOUT For infra, Enjoy!!!
OID @vm-oid.banglalinkgsm.com:/u02/infra/product/104/orcl$
2 Likes

Are you planning to generate new key pairs and test them to ensure they are working properly?

Or did I misunderstand you?

Thanks for showing the ssh log. As it shows the same behaviour as the sftp login, we can be sure the error is not there. Still it's a good idea to implement the public keys. For your sftp problrm: Go along the line stomp proposed; I was going to answer the same as I had a similar problem some years ago, but just wanted to double check before posting.

Hi Stomp and Rudic,

This is the output i got as per Stomp proposed. Please share us next wayaround.

OID @vm-oid.banglalinkgsm.com:/home/infra$ssh infra@172.16.10.179 /usr/bin/true
infra@172.16.10.179's password:
NO TIMEOUT For infra, Enjoy!!!
bash: /usr/bin/true: No such file or directory
OID @vm-oid.banglalinkgsm.com:/home/infra$

So, what from the link posted by stomp did you try / incorporate / implement?