Hi,
i have implemented Password-less ssh to my server.
Now i can ssh to my server but i cant do scp to my server.
But i can scp from my server machine to client

Have you set password-less SSH from client to server? If so, password-less SSH from client to server is working?

I have set passwordless ssh from client to server.
Now ssh is working from client to server but scp is not working

Can you please paste the ssh and scp commands you're trying?

ravishankaradepu@ravishankaradepu-CELSIUS-M470-2:~$ ssh -v printer@192.168.4.151
OpenSSH_5.8p1 Debian-1ubuntu3, OpenSSL 0.9.8o 01 Jun 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 192.168.4.151 [192.168.4.151] port 22.
debug1: Connection established.
debug1: identity file /home/ravishankaradepu/.ssh/id_rsa type 1
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
debug1: identity file /home/ravishankaradepu/.ssh/id_rsa-cert type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_dsa type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_dsa-cert type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_ecdsa type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.5p1 Debian-4ubuntu6
debug1: match: OpenSSH_5.5p1 Debian-4ubuntu6 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.8p1 Debian-1ubuntu3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr 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: Server host key: RSA 52:7c:ec:27:16:f0:d7:5c:1c:56:b6:a8:79:d7:c1:e4
debug1: Host '192.168.4.151' is known and matches the RSA host key.
debug1: Found key in /home/ravishankaradepu/.ssh/known_hosts:9
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/ravishankaradepu/.ssh/id_rsa
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug1: Authentication succeeded (publickey).
Authenticated to 192.168.4.151 ([192.168.4.151]:22).
debug1: channel 0: new [client-session]
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug1: Remote: Forced command: /usr/local/sbin/log-session
debug1: Remote: Forced command: /usr/local/sbin/log-session
debug1: Sending environment.
debug1: Sending env LC_MESSAGES = en_IN.UTF-8
debug1: Sending env LANG = en_IN
printer@printer-CELSIUS-M470-2:~$


ravishankaradepu@ravishankaradepu-CELSIUS-M470-2:~$ scp -v My_cv.doc printer@192.168.4.151:.
Executing: program /usr/bin/ssh host 192.168.4.151, user printer, command scp -v -t -- .
OpenSSH_5.8p1 Debian-1ubuntu3, OpenSSL 0.9.8o 01 Jun 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 192.168.4.151 [192.168.4.151] port 22.
debug1: Connection established.
debug1: identity file /home/ravishankaradepu/.ssh/id_rsa type 1
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
debug1: identity file /home/ravishankaradepu/.ssh/id_rsa-cert type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_dsa type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_dsa-cert type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_ecdsa type -1
debug1: identity file /home/ravishankaradepu/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.5p1 Debian-4ubuntu6
debug1: match: OpenSSH_5.5p1 Debian-4ubuntu6 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.8p1 Debian-1ubuntu3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr 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: Server host key: RSA 52:7c:ec:27:16:f0:d7:5c:1c:56:b6:a8:79:d7:c1:e4
debug1: Host '192.168.4.151' is known and matches the RSA host key.
debug1: Found key in /home/ravishankaradepu/.ssh/known_hosts:9
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/ravishankaradepu/.ssh/id_rsa
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug1: Authentication succeeded (publickey).
Authenticated to 192.168.4.151 ([192.168.4.151]:22).
debug1: channel 0: new [client-session]
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug1: Remote: Forced command: /usr/local/sbin/log-session
debug1: Remote: Forced command: /usr/local/sbin/log-session
debug1: Sending environment.
debug1: Sending env LC_MESSAGES = en_IN.UTF-8
debug1: Sending env LANG = en_IN
debug1: Sending command: scp -v -t -- .
Sending file modes: C0644 28672 My_cv.doc
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug1: client_input_channel_req: channel 0 rtype eow@openssh.com reply 0
debug1: channel 0: free: client-session, nchannels 1
debug1: fd 0 clearing O_NONBLOCK
debug1: fd 1 clearing O_NONBLOCK
Transferred: sent 2752, received 2408 bytes, in 0.2 seconds
Bytes per second: sent 15039.6, received 13159.6
debug1: Exit status 0
lost connection

it looks like a problem on the other side. Probably scp cannot write the file or ??? Can you check the logs on that host also?

I checked /var/log/syslog but it dosent have anything there...!!

I got the problem
When ever i am ssh using password less ssh , i use forced command to store the session to a file. I use the following script to do that.
Now what should i do to do this for scp also??

#!/bin/sh
#
# log-session
# John Simpson <jms1@jms1.net> 2008-08-06
#
###############################################################################
#
# Copyright (C) 2008 John Simpson.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 3, as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
###############################################################################
#
# configuration

# copy this value from the "Subsystem sftp" line in your sshd_config file
SFTP_SERVER=/usr/lib/openssh/sftp-server

###############################################################################
###############################################################################
###############################################################################

NOW=`date +%Y-%m-%d.%H%M%S`
IP=`echo $SSH_CLIENT | sed 's/ .*//'`
#LOGFILE=/root/.ssh/log.$NOW.$IP
LOGFILE=/home/printer/.ssh/log.$NOW.$IP
# if you want to log the initial contents of the environment received from
# sshd, un-comment these lines.
#
# env | sort >> $LOGFILE
# echo "========================================" >> $LOGFILE

# the "internal-sftp" service is new as of openssh 5.0. it works like
# the sftp server logic is built into sshd, and as such it's capable of
# chroot'ing users into their home directories.
# there's no way to "redirect" execution back into it, so the best we
# can do is exec the old sftp-server instead, which will give the user a
# working sftp session, but won't chroot them into their home directory.

if [ "${SSH_ORIGINAL_COMMAND:-}" = "internal-sftp" ]
then
echo "substituting $SFTP_SERVER for internal SFTP service" >> $LOGFILE
echo "========================================" >> $LOGFILE
exec $SFTP_SERVER

# if they're requesting the sftp server, this is an sftp command.
# logging the traffic wouldn't make much sense, it's a binary protocol...
# although if you really want to log the raw data, comment out this block
# and let execution fall through to the next block.

elif [ "${SSH_ORIGINAL_COMMAND:-}" = "$SFTP_SERVER" ]
then
echo starting SFTP service >> $LOGFILE
echo ======================================== >> $LOGFILE
exec $SFTP_SERVER

# if the user asked for a specific command, run that command
# but log the traffic going into and out of it.

elif [ -n "${SSH_ORIGINAL_COMMAND:-}" ]
then
echo executing $SSH_ORIGINAL_COMMAND >> $LOGFILE
echo ======================================== >> $LOGFILE
exec script -a -f -q -c "$SSH_ORIGINAL_COMMAND" $LOGFILE

# no command was requested, user wants an interactive shell.
# of course, log the traffic going in and out of it.

else
echo starting interactive shell session >> $LOGFILE
echo ======================================== >> $LOGFILE
exec script -a -f -q $LOGFILE
fi

# if we get to this point, an "exec" failed somewhere.

echo exec failed, rv=$?
exit 1

what I see is: scp looks for authentication in /home/ravishankaradepu but it wants to write into the home of printer. Try to execute
scp My_cv.doc printer@192.168.4.151:/tmp, use full path, instead of .

Same Lost connection is being outputted

Oh yes, that can be a problem also. this log-session started by scp also, you can see it in the debug log. This shell script will write log to /home/printer/.ssh/log.$NOW.$IP. You can check the content.

1 members found this post helpful.

What changes should be done to the log-session ??

I do not know what's happened, so would be better to see the log

1 members found this post helpful.

One line was written to the file , but it was not readable

you can insert a line into that log-session script:
and test it again. That one line is not an acceptable result.
Also you can try to move it:
LOGFILE=/tmp/sshlog.$NOW.$IP