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bergqvistjl

Member

Registered: 2011-01-05

Posts: 55

SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

somehow X11 Forwarding has over SSH stopped working on my server - MobaXterm tells me that it's "disabled or not supported by server".

This is my SSHD_config:

#       $OpenBSD: sshd_config,v 1.90 2013/05/16 04:09:14 dtucker Exp $

# This is the sshd server system-wide configuration file.  See
# sshd_config(5) for more information.

# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin

# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented.  Uncommented options override the
# default value.

Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::

# The default requires explicit activation of protocol 1
#Protocol 2

# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_dsa_key
#HostKey /etc/ssh/ssh_host_ecdsa_key
#HostKey /etc/ssh/ssh_host_ed25519_key

# Lifetime and size of ephemeral version 1 server key
#KeyRegenerationInterval 1h
#ServerKeyBits 1024

# Ciphers and keying
#RekeyLimit default none

# Logging
# obsoletes QuietMode and FascistLogging
#SyslogFacility AUTH
#LogLevel INFO

# Authentication:

#LoginGraceTime 2m
#PermitRootLogin prohibit-password
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

#RSAAuthentication yes
#PubkeyAuthentication yes

# The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2
# but this is overridden so installations will only check .ssh/authorized_keys
AuthorizedKeysFile      .ssh/authorized_keys

#AuthorizedPrincipalsFile none

#AuthorizedKeysCommand none
#AuthorizedKeysCommandUser nobody

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

# To disable tunneled clear text passwords, change to no here!
#PasswordAuthentication yes
#PermitEmptyPasswords no

# Change to no to disable s/key passwords
ChallengeResponseAuthentication no

# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

# 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

#AllowAgentForwarding yes
AllowTcpForwarding yes
#GatewayPorts no
X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost yes
#PermitTTY yes
PrintMotd no # pam does that
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#UsePrivilegeSeparation sandbox
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS no
#PidFile /run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none
#VersionAddendum none

# no default banner path
#Banner none

# override default of no subsystems
Subsystem       sftp    /usr/lib/ssh/sftp-server

# Example of overriding settings on a per-user basis
#Match User anoncvs
#       X11Forwarding no
#       AllowTcpForwarding no
#       PermitTTY no
#       ForceCommand cvs server

What have I done wrong?

my $DISPLAY variable is empty whenever i log in

paulkerry

Member

From: Sheffield, UK

Registered: 2014-10-02

Posts: 611

Re: SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

Do you have xauth installed on your server? It's in the xorg-xauth package.

bergqvistjl

Member

Registered: 2011-01-05

Posts: 55

Re: SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

Do you have xauth installed on your server? It's in the xorg-xauth package.

Yes. I don't have an .Xauthority file at the user i'm connecting to SSH under though. Should I have one, and how do I create it?

qinohe

Member

From: Netherlands

Registered: 2012-06-20

Posts: 1,494

Re: SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

Install xorg-xauth.

touch .Xauthority && chmod 600 .Xauthority

should do the trick;)

bergqvistjl

Member

Registered: 2011-01-05

Posts: 55

Re: SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

Install xorg-xauth.

touch .Xauthority && chmod 600 .Xauthority

should do the trick;)

Nope, done that but it's still saying X11-forwarding is disabled or not supported by the server. My $DISPLAY is still empty.

Update: I changed

#AddressFamily any

to

AddressFamily inet

in my ssh config file and it's working again. Thanks!

Last edited by bergqvistjl (2016-10-24 12:43:59)

qinohe

Member

From: Netherlands

Registered: 2012-06-20

Posts: 1,494

Re: SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

You solved it nice

Last edited by qinohe (2016-10-24 13:00:35)

qinohe

Member

From: Netherlands

Registered: 2012-06-20

Posts: 1,494

Re: SSH X11 Fowarding no longer working - MobaXterm says it's not enabled

Sorry dubble post)

edit: 'any' should work though, unless you blacklisted ipv6.

Last edited by qinohe (2016-10-24 13:11:20)