Subject: Bug#1173: stDXFCE_dp24: is blocked

From: Felix B. Müller <[email-masked]>
Date: Fri, 5 May 2017 16:57:59 +0200

Package: x2go-server

Version: 4.0.1.20

Dear all,

I have an Ubuntu 16.04.2 LTS (Server) which is integrated in the Windows
Active Directory (AD). The user authentification is done via Kerberos
followed here:

https://help.ubuntu.com/community/ActiveDirectoryWinbindHowto

The directories are also mounted automatically every time the user logs on
via pam_mount:

  <volume user="*" fstype="cifs" server="fileserver1"
path="home/%(DOMAIN_USER)" mountpoint="/home/%(DOMAIN_USER)"/>

This works quite nice and I can login via ssh with the user names of the AD.
I also would like to use x2go for the AD users. However, it works fine when
I try to connect to the server (called ssh or ssh2) from the internal
network (192.168.0.0). The users get their remote desktops. However, if they
try to login remotely from another subnet the session could not be
initialized. I was looking for the problem the last 3 weeks. Of course the
first idea was due to a misconfigured firewall.

The configuration is as follows:

INTERNET ----- NAT1 -----(192.168.183.0)------  NAT2 ----(192.168.0.0)------
ssh-server 

I replaced the firewall, I put the PC (ssh-server) directly after the NAT. I
had a look in all network connections with wireshark. I opened all ports.
None of these things solved the problem. However, I can login with a local
user (user account on the ssh-server) on the ssh-server but not with a user
of the AD (username test01). I set the logging to the debug mode and I see
that a file is always blocked. I do not understand why this file is blocked
if I login from another subnet. Maybe this is not a bug – I do not know and
I do not understand this behavior.

May  5 16:08:41 ssh2 /usr/sbin/x2gocleansessions[1717]:
test01-50-1493993318_stDXFCE_dp24: updating session status from 'R' to 'F'.

May  5 16:08:41 ssh2 /usr/sbin/x2gocleansessions[1717]:
test01-50-1493993318_stDXFCE_dp24: is blocked.

May  5 16:08:41 ssh2 /usr/sbin/x2gocleansessions[1717]:
test01-50-1493993318_stDXFCE_dp24: adding to finished list.

May  5 16:08:41 ssh2 /usr/bin/x2goumount-session[11035]: x2goumount-session
has been called with options:

Best regards!