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Normally, when I'm logged into a remote machine and want the
display to display to my machine, I use xhost to add the remote
machine to the list of authorized machines and export DISPLAY
on the remote machine to be my machine.

Today, I noticed that on both of my gentoo machines (one laptop and
one desktop) this doesn't seem to work. For example, if I do
'xhost 127.0.0.1' and 'export DISPLAY=127.0.0.1:0' and then
try to run xclock, nothing happens for about 6 seconds and then
I receive the error message: "Error: Can't open display: 127.0.0.1:0"

Running nmap against both machines reveals that X11 isn't listening
on the usual port (6000?). Did I fail to configure X correctly or
is there some step I still need to take in order to use my gentoo
machines as remote X display?

Any help will be appreciated.

--Dan

So anyway, it was like, 00:16 CET Dec 04 2003, you know? Oh, and, yeah,
Dan was all like, "Dude,

> Normally, when I'm logged into a remote machine and want the display
> to display to my machine, I use xhost to add the remote machine to
> the list of authorized machines and export DISPLAY on the remote
> machine to be my machine.

Using ssh to accomplish this will both be easier and more secure.

'man ssh'

hth.

--
Time flies like an arrow, fruit flies like a banana. Perth ---> *
00:25:03 up 5 days, 5:42, 5 users, load average: 3.11, 3.34, 3.12
$ cat /dev/bollocks Registered Linux user #261729
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Dan <daniel_a_ost@yahoo.com> randomly warbled in alt.os.linux.gentoo:

> Normally, when I'm logged into a remote machine and want the
> display to display to my machine, I use xhost to add the remote
> machine to the list of authorized machines and export DISPLAY
> on the remote machine to be my machine.
>
> Today, I noticed that on both of my gentoo machines (one laptop and
> one desktop) this doesn't seem to work. For example, if I do
> 'xhost 127.0.0.1' and 'export DISPLAY=127.0.0.1:0' and then
> try to run xclock, nothing happens for about 6 seconds and then
> I receive the error message: "Error: Can't open display: 127.0.0.1:0"
>
> Running nmap against both machines reveals that X11 isn't listening
> on the usual port (6000?). Did I fail to configure X correctly or
> is there some step I still need to take in order to use my gentoo
> machines as remote X display?

If you want X to display on a remote system what makes you think that
using 127.0.0.1 will ever work ?
This is an IP standard address meaning "this machine only" and is NEVER
ever visible from any other machine - since it means "me" on any other
machine as well...

Even though it is an IP address, many not-old-hands fail to understand
that 127.0.01 is NOT a network address - it uses the network
*protocols*, but nothing is sent out over any wire - ever.

Don't run nmap "against all machines", this is silly - use netstat.

Also check with netstat -ltp whether X is listening anywhere at all on
the machine, and add the appropriate network(s) you want to conenct
from (to xhost? I don't use this meself, I'm a VNC junkie ;-)

--
Jeroen Geilman

All your bits are belong to us.

Johan Lindquist <spam@smilfinken.net> wrote in message news:<s082a1-reb.ln1@news.smilfinken.net>...
> So anyway, it was like, 00:16 CET Dec 04 2003, you know? Oh, and, yeah,
> Dan was all like, "Dude,
>
> > Normally, when I'm logged into a remote machine and want the display
> > to display to my machine, I use xhost to add the remote machine to
> > the list of authorized machines and export DISPLAY on the remote
> > machine to be my machine.
>
> Using ssh to accomplish this will both be easier and more secure.
>
> 'man ssh'

I agree that ssh is a better solution and it works fine when the
machine I'm interested in has ssh. However, some machines don't
and so for those machines I need another solution.

Using X for remote display is a more generic solution that should
work anywhere.

--Dan

Jeroen Geilman <nospam@notadaptr.nl> wrote in message news:<3fce7241$0$211$e4fe514c@news.xs4all.nl>...
>
> If you want X to display on a remote system what makes you think that
> using 127.0.0.1 will ever work ?
> This is an IP standard address meaning "this machine only" and is NEVER
> ever visible from any other machine - since it means "me" on any other
> machine as well...

I didn't want to post a real IP address and so I used
the loopback address in my example. I appologize for my
bad example, but the behavior is the same regardless of
IP used.

> Also check with netstat -ltp whether X is listening anywhere at all on
> the machine, and add the appropriate network(s) you want to conenct
> from (to xhost? I don't use this meself, I'm a VNC junkie ;-)

This, I believe, is the crux of my problem: X11 is not listening on port 6000
of my gentoo boxes. With other distibutions, this is default bahavior, but
apparently it's not default for X running on gentoo. What do I need to do
to get X11 listening on port 6000?

--Dan

So anyway, it was like, 15:17 CET Dec 04 2003, you know? Oh, and, yeah,
Dan was all like, "Dude,

> This, I believe, is the crux of my problem: X11 is not listening
> on port 6000 of my gentoo boxes. With other distibutions, this is
> default bahavior, but apparently it's not default for X running on
> gentoo. What do I need to do to get X11 listening on port 6000?

Somewhere in a config file you will likely find a line contaning

/usr/X11R6/bin/X -nolisten tcp

If you're using gdm, it will be in /etc/X11/gdm/gdm.conf.

Removing the "-nolisten tcp" part might do the trick.

I still think you should use ssh tho, and install an ssh daemon rather
than transport your information back and forth in clear text.

--
Time flies like an arrow, fruit flies like a banana. Perth ---> *
18:22:23 up 16:27, 6 users, load average: 2.11, 2.13, 2.18
$ cat /dev/bollocks Registered Linux user #261729
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On Thu, 04 Dec 2003 06:17:29 -0800, Dan wrote:

> This, I believe, is the crux of my problem: X11 is not listening on port 6000
> of my gentoo boxes. With other distibutions, this is default bahavior, but
> apparently it's not default for X running on gentoo. What do I need to do
> to get X11 listening on port 6000?

Probably because there is a message at the end of emerge xfree that says:
#tail -n 20 /usr/portage/x11-base/xfree/xfree-4.3.0-r3.ebuild
ewarn "Listening on tcp is disabled by default with startx."
ewarn "To enable it, edit /usr/X11R6/bin/startx."

On Thu, 04 Dec 2003 18:29:01 +0100, Johan Lindquist wrote:

>> This, I believe, is the crux of my problem: X11 is not listening
>> on port 6000 of my gentoo boxes. With other distibutions, this is
>> default bahavior, but apparently it's not default for X running on
>> gentoo. What do I need to do to get X11 listening on port 6000?
>
> Somewhere in a config file you will likely find a line contaning
>
> /usr/X11R6/bin/X -nolisten tcp
>
> If you're using gdm, it will be in /etc/X11/gdm/gdm.conf.
>
> Removing the "-nolisten tcp" part might do the trick.

correct, Gentoo has changed the default behavior.
by default, X will not listen on TCP sockets. the obvious reason is
security.
many users may never use the feature and many users probably dont even
know that you COULD do that
so why enable this feature ?
and if you want it, read the message as PiotrAF suggested and change it
yourself.
-mike

PiotrAF <piotraf@nospam.poczta.onet.pl> wrote in message news:<pan.2003.12.04.17.41.15.183714@nospam.poczta .onet.pl>...
> On Thu, 04 Dec 2003 06:17:29 -0800, Dan wrote:
>
> > This, I believe, is the crux of my problem: X11 is not listening on port 6000
> > of my gentoo boxes. With other distibutions, this is default bahavior, but
> > apparently it's not default for X running on gentoo. What do I need to do
> > to get X11 listening on port 6000?
>
> Probably because there is a message at the end of emerge xfree that says:
> #tail -n 20 /usr/portage/x11-base/xfree/xfree-4.3.0-r3.ebuild
> ewarn "Listening on tcp is disabled by default with startx."
> ewarn "To enable it, edit /usr/X11R6/bin/startx."

Yes, that was it. I had noticed this morning that it worked if I used
xinit but not if I used startx. Made a small edit to startx and all
my issues went away.

Thanks for your help!

--Dan

On Fri, 05 Dec 2003 07:18:55 -0800, Dan wrote:

> Thanks for your help!
Glad to hear that