View Issue Details

IDProjectCategoryView StatusLast Update
0002391CentOS-5-OTHERpublic2013-11-14 18:18
Reportertps800 
PrioritynormalSeveritymajorReproducibilityalways
Status assignedResolutionopen 
Product Version5.0 - i386 
Target VersionFixed in Version 
Summary0002391: SSH X11-Forwarding does not work
Description/etc/ssh/sshd_config:
[...]
X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost yes
[...]

on Client side:
[...]
ForwardX11 yes
ForwardX11Trusted yes
[...]

Then
> ssh -XYl user host
> echo $DISPLAY

>

Variable is empty. X11-Forwarding fails.
Additional InformationX11 forwarding does not work.
TagsNo tags attached.

Activities

Evolution

Evolution

2007-10-16 18:18

administrator   ~0006142

You're missing xorg-x11-xauth. Install this package.
herrold

herrold

2007-10-16 18:53

reporter   ~0006143

is xorg-x11-xauth installed (C5)?
JohnnyHughes

JohnnyHughes

2007-10-17 07:30

administrator   ~0006145

For the record ...

[johnny@myth ~]$ ssh -X -Y -l buildsvn 192.168.0.68
Last login: Sat Sep 22 07:30:22 2007 from myth.home.local

[buildsvn@c5-i386-build ~]$ echo $DISPLAY
localhost:10.0
wibbit

wibbit

2008-03-05 16:42

reporter   ~0006983

Hi All

I just wanted to confirm that I am suffering from this same problem.

rpm -q xorg-x11-xauth openssh
xorg-x11-xauth-1.0.1-2.1
openssh-4.3p2-24.el5

grep X11 /etc/ssh/sshd_config
#X11Forwarding no
X11Forwarding yes
#X11DisplayOffset 10
#X11UseLocalhost yes

[user@client ~]$ ssh -Y user@server
[user@server ~]$ echo $DISPLAY

[user@server ~]$

rpm -q centos-release
centos-release-5-1.0.el5.centos.1
tps800

tps800

2008-03-05 19:14

reporter   ~0006986

Yes, this was the solution to my problem. After installing xorg-x11-auth X11 forwarding began to work!
wibbit

wibbit

2008-03-05 19:29

reporter   ~0006988

Unfortunately, this does not resolve the problem for me.
tru

tru

2008-03-10 17:44

administrator   ~0007012

wibbit: is your **initial** DISPLAY set?
wibbit

wibbit

2008-03-10 19:28

reporter   ~0007014

On the machine that I'm ssh'ing from (the client) DISPLAY is set.

Also, if I manually add DISPLAY=localhost:10.0 every thing works as expected.
wibbit

wibbit

2008-03-19 10:37

reporter   ~0007044

Some additional information on this.

It would appear that on the box that is causing the problem, the SSH_TTY environment variable is not being set.

Does this help?

Is there any more information I can provide?
wibbit

wibbit

2008-04-05 11:04

reporter   ~0007101

Is there any other information that I can provide on this?
twwbond

twwbond

2009-05-18 20:04

reporter   ~0009366

Had same problem as wibbit. Issue for me was resolved by adding xauth package. You can see this by doing a ssh -X -v remote
uppercasek

uppercasek

2011-09-14 15:05

reporter   ~0013256

I know this issue is two years old, but the problem is because xauth's install path differs from where sshd is looking.

local$ ssh -vXY user@host.com
debug1: Requesting X11 forwarding with authentication spoofing.
debug1: Remote: No xauth program; cannot forward with spoofing.
remote$ echo $DISPLAY

remote$ strings /usr/sbin/sshd |grep xauth
/usr/X11R6/bin/xauth
remote$ ls -l /usr/X11R6/bin/xauth
ls: /usr/X11R6/bin/xauth: No such file or directory
remote$ rpm -ql xorg-x11-xauth | grep bin/xauth
/usr/bin/xauth
remote$ ln -s /usr/bin/xauth /usr/X11R6/bin/xauth
remote$ logout
local$ ssh -vXY user@host.com
debug1: Requesting X11 forwarding with authentication spoofing.
/usr/X11R6/bin/xauth: creating new authority file /home/user/.Xauthority
remote$ echo $DISPLAY
localhost:10.0

hope we can close out this issue now
wibbit

wibbit

2011-09-14 15:16

reporter   ~0013257

Aha! well spotted.

I wonder why for some people "it worked" after installing xauth, yet for others it did not?

As xauth was certainly installed on that system (of course I've now gone through 2 jobs since originally posting this, so there is no chance of getting access to the original issue/box I had).
uppercasek

uppercasek

2011-09-14 15:34

reporter   ~0013258

depends on the version of openssh

openssh-5.8p1 has this problem and possibly some older versions of openssh 5.x. i do not have this problem on any centos 5.6 or 6.0 boxes.
bevan

bevan

2012-04-03 21:12

reporter   ~0014786

It's IPV6. I just had this same issue.

Out-of-box CentOS6.2 - everything worked fine. I configured my normal settings, including adding "net.ipv6.conf.all.disable_ipv6 = 1" to /etc/sysctl.conf (The recommended way to turn it off according to the docs).

But now sshd keeps trying to bind ::1 and failing. The solution was to change "AddressFamily any" to "AddressFamily inet" in /etc/ssh/sshd_config and restart ssh. Voila!
GeneBean

GeneBean

2012-10-09 15:18

reporter   ~0015902

I had this same issue but made the "AddressFamily inet" change mentioned by bevan and that fixed it.
uppercasek

uppercasek

2012-10-09 15:57

reporter   ~0015905

Bevan and GeneBean's problem are related to CentOS-6, the initial issue had to do with CentOS-5 and specifically the openssh-5.8p1 package. If this is still an issue for folks, I will happily do a regression test with all versions of CentOS from 5.6 through 6-current.
tru

tru

2013-01-31 20:08

administrator   ~0016374

my 2 cents: I just hit the issue.

client: CentOS-5 openssh-4.3p2-82.el5.x86_64
remote server: CentOS-6 openssh-server-5.3p1-81.el6_3.x86_64, xorg-x11-xauth-1.0.2-7.1.el6.x86_64

default /etc/ssh/sshd_config reads:
...
#AddressFamily any
...

-> no X forwarding even if running ssh -X, ssh -Y or with "ForwardX11 yes" in ~/.ssh/config

Changing on the remote CentOS-6 server /etc/ssh/sshd_config:
"#AddressFamily any" -> "AddressFamily inet" for ipv4 only

-> X11 forwarding works and the xauth message is shown upon .Xauthority
creation:
/usr/bin/xauth: creating new authority file /home/tru/.Xauthority

imho, that's more a openssh-server "feature" on CentOS-6 than a bug on CentOS-5 at this time.
evgenyn

evgenyn

2013-11-14 09:36

reporter   ~0018351

I need to enable the X11 without reconnection to ssh.
Meaning I'm already connected to the server using : ssh root@server (without -X)
any way I can still use X11 or gnome??

Issue History

Date Modified Username Field Change
2007-10-16 18:05 tps800 New Issue
2007-10-16 18:18 Evolution Note Added: 0006142
2007-10-16 18:53 herrold Note Added: 0006143
2007-10-17 07:30 JohnnyHughes Note Added: 0006145
2007-10-17 07:32 JohnnyHughes Status new => assigned
2008-03-05 16:42 wibbit Note Added: 0006983
2008-03-05 19:14 tps800 Note Added: 0006986
2008-03-05 19:29 wibbit Note Added: 0006988
2008-03-10 17:44 tru Note Added: 0007012
2008-03-10 19:28 wibbit Note Added: 0007014
2008-03-19 10:37 wibbit Note Added: 0007044
2008-04-05 11:04 wibbit Note Added: 0007101
2009-05-18 20:04 twwbond Note Added: 0009366
2011-09-14 15:05 uppercasek Note Added: 0013256
2011-09-14 15:16 wibbit Note Added: 0013257
2011-09-14 15:34 uppercasek Note Added: 0013258
2012-04-03 21:12 bevan Note Added: 0014786
2012-10-09 15:18 GeneBean Note Added: 0015902
2012-10-09 15:57 uppercasek Note Added: 0015905
2013-01-31 20:08 tru Note Added: 0016374
2013-11-14 09:36 evgenyn Note Added: 0018351