Unable to connect to NX Server

[mt]

Hello,

I used NX3 for a long time and now just switched to NX4.
I have problems connecting to my server.

I understood the free NX suite does support only one user and no connection over ssh.
I’m connecting to a remote machine where I only have ssh access on port 22. To connect to the server I forwarded the remote port 4000 to a local port 4444 on the machine I’m running the client on.

I can connect to the remote machine by changing the nomachine port to 4444 and specifying localhost but I only get the NoMachine screen listing users where I see one user listed, when I disconnect it it disconnects my own session.

Is there something I’m doing wrong or misunderstanding some new feature?

Thks,

Michal

[titan]

Are you sure you installed the the free version? Can you see what –version says?

> /usr/NX/bin/nserver –version

With the free version, the server should connect you to the local screen (:0) without returning the list first.

when I disconnect it it disconnects my own session

I don’t understand this, I’m afraid. Can you post a screenshot of what you see in the client?

[mt]

I didn’t notice a separate package for the free version.
I downloaded mine from this link:
https://www.nomachine.com/select-package&prod=nomachine

Here is the version info:
/usr/NX/bin/nxserver –version
NoMachine – Version 4.0.362

I attached the screen I see when connecting to the machine.
I see there in the server status tab my own user connected at the same time as my only connection attempt.
I understand this list as a list of users connected before on the machine. I tough as the free version is mono-user I should try to disconnect the user I see in the list. But I’m getting disconnected, so it seems I’m disconnecting myself.

Note that I’m doing all this over ssh port forwarding of the server port 4000 on my local machine port 4444. I did forward only the TCP port 4000 but in the “connection information” menu of the NX Client I see “NX on port 4444 with RT port 4969” the 4444 is the forwarder server port 4000 but the “RT port 4969” is my local port on the local server which is also running (I think). Can’t this be a problem?

I’m attaching also the connection information screen.

Attachments:

1. 

   S3-New-11052013-13.33.03.png
   

2. 

   S3-New-Connection-information.png
   

[titan]

It seems to me that NoMachine is running fine but the problem is that no desktop environment is running on that X display.

Try pointing at that display and run something, like xterm. See if the xterm window comes up and it is displayed correctly.

[mt]

You are right
DISPLAY=:0 xterm
opens the xterm on the NX screen and works ok.

How do I check what NX executes to start the desktop environment?
It is a quite old OpenSusue 10.3 box I’m trying to connect to.

[mt]

I rebooted the server and the behavior changes a little.
The first time I connect to the server I get the KDE user login/pass screen. I log on and the session hangs/disconnects.
When I try to reconnect I get the behavior described in my first post.
Seems like the first session is somehow opened but I’m unable to use it neither reconnect to it later.
It seems to me similar to what another user described recently on the forum.

[mt]

In fact it seems it is a segfault. I see this in the system log:

Nov 5 14:47:37 linux-ypbf nxexec: PAM unable to dlopen(/lib64/security/pam_pwcheck.so)
Nov 5 14:47:37 linux-ypbf nxexec: PAM [error: /lib64/security/pam_pwcheck.so: undefined symbol: pam_syslog]
Nov 5 14:47:37 linux-ypbf nxexec: PAM adding faulty module: /lib64/security/pam_pwcheck.so
Nov 5 14:48:00 linux-ypbf kernel: drkonqi[4477]: segfault at 0000135d8a594908 rip 00002ae35433c558 rsp 00007fff797eb7b0 error 6
Nov 5 14:48:04 linux-ypbf kernel: drkonqi[4483]: segfault at 0000135d8a594908 rip 00002b2b40fc5558 rsp 00007fff62770590 error 6
Nov 5 14:48:05 linux-ypbf kernel: drkonqi[4490]: segfault at 0000135d8a594908 rip 00002b40278f3558 rsp 00007fff216c7530 error 6
Nov 5 14:48:05 linux-ypbf kernel: kicker[4491]: segfault at 0000135d8a594908 rip 00002b32ea8f0558 rsp 00007fff9e445c40 error 6
Nov 5 14:48:14 linux-ypbf kernel: drkonqi[4589]: segfault at 0000135d8a594908 rip 00002b96975c8558 rsp 00007fffb4eab960 error 6
Nov 5 14:48:24 linux-ypbf kernel: drkonqi[4617]: segfault at 0000135d8a594908 rip 00002ae929c4c558 rsp 00007fff5f0464f0 error 6
Nov 5 14:48:24 linux-ypbf kernel: drkonqi[4618]: segfault at 0000135d8a594908 rip 00002ad3d91c6558 rsp 00007fffccea7600 error 6
Nov 5 14:48:24 linux-ypbf kernel: drkonqi[4620]: segfault at 0000135d8a594908 rip 00002b06849e1558 rsp 00007fffc80297c0 error 6
Nov 5 14:48:25 linux-ypbf kernel: drkonqi[4619]: segfault at 0000135d8a594908 rip 00002aba5a773558 rsp 00007fff010e7b90 error 6
Nov 5 14:48:25 linux-ypbf kernel: drkonqi[4625]: segfault at 0000135d8a594908 rip 00002b0683dc9558 rsp 00007fff17b43420 error 6
Nov 5 14:48:25 linux-ypbf kernel: drkonqi[4629]: segfault at 0000135d8a594908 rip 00002ad0eb3e5558 rsp 00007fffee313cd0 error 6
Nov 5 14:48:25 linux-ypbf kernel: drkonqi[4630]: segfault at 0000135d8a594908 rip 00002b04f86d3558 rsp 00007fffa713db30 error 6
Nov 5 14:48:25 linux-ypbf kernel: drkonqi[4634]: segfault at 0000135d8a594908 rip 00002abee2406558 rsp 00007fffd13e4e50 error 6
Nov 5 14:48:25 linux-ypbf kernel: drkonqi[4636]: segfault at 0000135d8a594908 rip 00002b601712e558 rsp 00007fff765a1ca0 error 6
Nov 5 14:48:28 linux-ypbf nxexec: PAM unable to dlopen(/lib64/security/pam_pwcheck.so)
Nov 5 14:48:28 linux-ypbf nxexec: PAM [error: /lib64/security/pam_pwcheck.so: undefined symbol: pam_syslog]
Nov 5 14:48:28 linux-ypbf nxexec: PAM adding faulty module: /lib64/security/pam_pwcheck.so
Nov 5 14:48:28 linux-ypbf kernel: drkonqi[4665]: segfault at 0000135d8a594908 rip 00002ac3b1564558 rsp 00007fff1aa97950 error 6
Nov 5 14:48:28 linux-ypbf kernel: drkonqi[4667]: segfault at 0000135d8a594908 rip 00002b8f021be558 rsp 00007ffffe6cd2d0 error 6
Nov 5 14:48:28 linux-ypbf kernel: drkonqi[4671]: segfault at 0000135d8a594908 rip 00002b5f89f2d558 rsp 00007fff8cfb24e0 error 6
Nov 5 14:48:40 linux-ypbf python: hp-systray(qt4)[4640]: error: No system tray detected on this system. Unable to start, exiting.
Nov 5 14:48:40 linux-ypbf kernel: python[4640]: segfault at 0000135d8a59490c rip 00002b45ce7823da rsp 00007fff847e08c8 error 4

[titan]

OK, interesting. I’m not sure we have the possibility to test on a OpenSUSE 10.3 and I’m not sure I understand what’s happening here but I’m passing the info.

Thanks.

[mt]

I’m not 100% certain it is a X problem.

As the syslog lines
Nov 5 17:16:44 linux-ypbf nxexec: PAM unable to dlopen(/lib64/security/pam_pwcheck.so)
Nov 5 17:16:44 linux-ypbf nxexec: PAM [error: /lib64/security/pam_pwcheck.so: undefined symbol: pam_syslog]
Nov 5 17:16:44 linux-ypbf nxexec: PAM adding faulty module: /lib64/security/pam_pwcheck.so

are suggesting it seems to be a pam problem.

And de facto the pam module on my distro seems buggy
ldd -r /lib64/security/pam_pwcheck.so
undefined symbol: pam_syslog (/lib64/security/pam_pwcheck.so)
undefined symbol: pam_set_data (/lib64/security/pam_pwcheck.so)
undefined symbol: pam_get_item (/lib64/security/pam_pwcheck.so)
undefined symbol: pam_vprompt (/lib64/security/pam_pwcheck.so)
undefined symbol: pam_set_item (/lib64/security/pam_pwcheck.so)
undefined symbol: pam_get_data (/lib64/security/pam_pwcheck.so)
undefined symbol: pam_prompt (/lib64/security/pam_pwcheck.so)
libdl.so.2 => /lib64/libdl.so.2 (0x00002b94f060f000)
libcrack.so.2 => /usr/lib64/libcrack.so.2 (0x00002b94f0813000)
libxcrypt.so.1 => /lib64/libxcrypt.so.1 (0x00002b94f0a20000)
libc.so.6 => /lib64/libc.so.6 (0x00002b94f0c5c000)
/lib64/ld-linux-x86-64.so.2 (0x0000555555554000)

As a check I’d like to avoid using the PAM module for authentication.
Is this possible with the free version?

I tried this in the config file:
diff /usr/NX/etc/server.cfg /usr/NX/etc/server.cfg.old
242c242
< EnableUserDB 0
—
> #EnableUserDB 0
266c266
< SSHDAuthServer 127.0.0.1
—
> #SSHDAuthServer 127.0.0.1
272c272
< SSHDAuthPort 22
—
> #SSHDAuthPort 22

But it does nothing.

[titan]

I log on and the session hangs/disconnects

Hmmm, it seems to me that it is working fine. As far as I can see it is not hanging or disconnecting.

It seems to me similar to what another user described recently on the forum.

I don’t think it’s the same problem. What is crashing here seems to be KDE, so the X server restarts (hence possibly the disconnect because there is no server anymore). Then, after the X server is restarted (by the system, because you are at runlevel 5) KDE hangs. Unfortunately I have seen problems like this many many times.

Nov 5 14:47:37 linux-ypbf nxexec: PAM unable to dlopen(/lib64/security/pam_pwcheck.so)
Nov 5 14:47:37 linux-ypbf nxexec: PAM [error: /lib64/security/pam_pwcheck.so: undefined symbol: pam_syslog]
Nov 5 14:47:37 linux-ypbf nxexec: PAM adding faulty module: /lib64/security/pam_pwcheck.so

I checked with the author of the nxexec module and that message is just PAM not finding one of its modules (something outside our control). It’s not a crash. I don’t even think it’s a real problem. Probably just some PAM auth methods that can’t be used. Anyway if nxexec can’t use PAM it will fall back to shadow passwd. The remaining crashes are from KDE. This is not to say that it can’t be a NoMachine bug, of course. It’s just that it’s difficult to say from 1000 miles away. You should ensure that everything else is working, that your desktop environment runs 100% OK, that your KDE and Xorg and drivers are up-to-date. Debugging X problems is always a tedious process.

[mt]

Ok so it seems I heve to fall back to NX3.5 on the server side.
I had this setup before, it worked fine (NX4 client to NX3.5 server) the onlye problem I had was that at every connection the previous session was not resumed but a new one was created.
Is there a way to avoid this?

[Britgirl]

Hi mt, can you post a new topic if you are having problems with resuming sessions on your 3.5.0 server? This way we don’t embed too many issues into one topic.

Thanks!

[titan]

Michal,

I’m sorry you decided to go back to the 3, especially because I don’t think what you experienced were really NoMachine problems. Anyway I’m afraid we can’t help you with the 3 version. This forum is only for the 4 users.

[Author]

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