Error: no display specified

["T. vor der Brück"]

Hi, together,

I make a remote login and try to start an x application I always get the
error message:
Error: no display specified

I use Debian Squeeze on both machines, the ssh client and the ssh
server, the error must be on the server-side since it works with other
Ubuntu SSH servers with this client. The package xauth is installed on
the server.

I provide the debug output of the ssh client and the sshd_config
Any help would be appreciated.

Tim

shell-debug
=======================================

vorderbr@pc-108-198:~$ ssh -vv -X -l vorderbr pc-108-214
OpenSSH_5.5p1 Debian-6+squeeze1, OpenSSL 0.9.8o 01 Jun 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to pc-108-214 [141.2.108.214] port 22.
debug1: Connection established.
debug1: identity file /home/vorderbr/.ssh/id_rsa type -1
debug1: identity file /home/vorderbr/.ssh/id_rsa-cert type -1
debug1: identity file /home/vorderbr/.ssh/id_dsa type -1
debug1: identity file /home/vorderbr/.ssh/id_dsa-cert type -1
debug1: Remote protocol version 2.0, remote software version
OpenSSH_5.5p1 Debian-6+squeeze1
debug1: match: OpenSSH_5.5p1 Debian-6+squeeze1 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.5p1 Debian-6+squeeze1
debug2: fd 3 setting O_NONBLOCK
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit:
diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit:
ssh-rsa-...@openssh.com,ssh-dss-...@openssh.com,ssh-rsa,ssh-dss
debug2: kex_parse_kexinit:
aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijnda...@lysator.liu.se
debug2: kex_parse_kexinit:
aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijnda...@lysator.liu.se
debug2: kex_parse_kexinit:
hmac-md5,hmac-sha1,uma...@openssh.com,hmac-ripemd160,hmac-ri...@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit:
hmac-md5,hmac-sha1,uma...@openssh.com,hmac-ripemd160,hmac-ri...@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zl...@openssh.com,zlib
debug2: kex_parse_kexinit: none,zl...@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-sha256,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-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijnda...@lysator.liu.se
debug2: kex_parse_kexinit:
aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijnda...@lysator.liu.se
debug2: kex_parse_kexinit:
hmac-md5,hmac-sha1,uma...@openssh.com,hmac-ripemd160,hmac-ri...@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit:
hmac-md5,hmac-sha1,uma...@openssh.com,hmac-ripemd160,hmac-ri...@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zl...@openssh.com
debug2: kex_parse_kexinit: none,zl...@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_setup: found hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: found hmac-md5
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
debug2: dh_gen_key: priv key bits set: 130/256
debug2: bits set: 537/1024
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host 'pc-108-214' is known and matches the RSA host key.
debug1: Found key in /home/vorderbr/.ssh/known_hosts:1
debug2: bits set: 513/1024
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: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/vorderbr/.ssh/id_rsa ((nil))
debug2: key: /home/vorderbr/.ssh/id_dsa ((nil))
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Trying private key: /home/vorderbr/.ssh/id_rsa
debug1: Trying private key: /home/vorderbr/.ssh/id_dsa
debug2: we did not send a packet, disable method
debug1: Next authentication method: password
vorderbr@pc-108-214's password:
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
debug1: channel 0: new [client-session]
debug2: channel 0: send open
debug1: Requesting no-more-...@openssh.com
debug1: Entering interactive session.
debug2: callback start
debug2: x11_get_proto: /usr/bin/xauth list :0.0 2>/dev/null
debug1: Requesting X11 forwarding with authentication spoofing.
debug2: channel 0: request x11-req confirm 0
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug1: Sending environment.
debug1: Sending env LANG = de_DE.utf8
debug2: channel 0: request env confirm 0
debug2: channel 0: request shell confirm 1
debug2: fd 3 setting TCP_NODELAY
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Linux pc-108-214 2.6.39-bpo.2-amd64 #1 SMP Tue Jul 26 10:35:23 UTC 2011
x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
You have new mail.
Last login: Fri Mar 9 12:17:57 2012 from pc-108-198
vorderbr@pc-108-214:~$ firefox
Error: no display specified
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0
vorderbr@pc-108-214:~$ debug2: client_check_window_change: changed
debug2: channel 0: request window-change confirm 0


sshd config
===========================
# Package generated configuration file
# See the sshd_config(5) manpage for details

# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes

# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768

# Logging
SyslogFacility AUTH
LogLevel INFO

# Authentication:
LoginGraceTime 120
PermitRootLogin yes
StrictModes yes

RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys

# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for
RhostsRSAAuthentication
#IgnoreUserKnownHosts yes

# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no

# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no

# Change to no to disable tunnelled clear text passwords
#PasswordAuthentication yes

# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

X11Forwarding yes
#AddressFamily inet
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no

#MaxStartups 10:30:60
#Banner /etc/issue.net

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

Subsystem sftp /usr/lib/openssh/sftp-server

# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
#ForwardX11 yes

[Aragorn]

On Friday 09 March 2012 11:25, T. vor der Brück conveyed the following
to comp.os.linux.x...

> Hi, together,
>
> I make a remote login and try to start an x application I always get
> the error message:
> Error: no display specified
>

> [...]

You have to export the DISPLAY variable on the remote machine so that it
points to your local machine's DISPLAY, and you must do this _before_
attempting to run a remote X application.

For instance...

export DISPLAY=192.168.0.1:0.0
----------- - -
| | |_ port on the local video adapter
| |___ local video adapter
|_________ local IP address or hostname

Hope this helps. ;-)

--
= Aragorn =
(registered GNU/Linux user #223157)

[Richard Kettlewell]

"T. vor der Brück" <nos...@nospam.de> writes:
> debug2: x11_get_proto: /usr/bin/xauth list :0.0 2>/dev/null
> debug1: Requesting X11 forwarding with authentication spoofing.
> debug2: channel 0: request x11-req confirm 0

The client has certainly asked for X11 forwarding.

> Linux pc-108-214 2.6.39-bpo.2-amd64 #1 SMP Tue Jul 26 10:35:23 UTC
> 2011 x86_64
>
> The programs included with the Debian GNU/Linux system are free software;
> the exact distribution terms for each program are described in the
> individual files in /usr/share/doc/*/copyright.
>
> Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
> permitted by applicable law.
> You have new mail.
> Last login: Fri Mar 9 12:17:57 2012 from pc-108-198
> vorderbr@pc-108-214:~$ firefox
> Error: no display specified

Is DISPLAY set or not at this point?

If not, is it possible that it's been modified in one of the shell
startup files?

> sshd config

Just to be clear, that is the server's sshd_config?

--
http://www.greenend.org.uk/rjk/

[Richard Kettlewell]

He's trying to use X11 forwarding, which does not in general need anyone
to mess around with DISPLAY variables.

--
http://www.greenend.org.uk/rjk/

[John McCue]

"T. vor der Bruck" <nos...@nospam.de> wrote:
> Hi, together,
>
> I make a remote login and try to start an x application I always get the
> error message:
> Error: no display specified

<snip>

Hi,

Give this a try:

1. add the 2 lines below to /etc/ssh/sshd_config

Match User <USERID>
X11Forwarding yes


2. execute
ssh -Y <USERID>@<SYS_NAME> -X
and see if it works, ssh will take care of DISPLAY

<USERID> =your user id
<SYS_NAME> = your remote system

HTH
John

[osval...@gmail.com]

If setting the DISPLAY on the remote machine didn't work for you, take a look at this: http://oroborosx.sourceforge.net/remotex.html
You might need to authorize the "Magic-Cookie" in the remote machine as well.