Ubuntu 15.04 64-bit desktop.

After install system X server run with -nolisten tcp option:

922 tty7 Ssl+ 0:05 \_ /usr/bin/X -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch

I add xserver-allow-tcp=true into /etc/lightdm/lightdm.conf and reboot. So X now started without -nolisten tcp:

2688 tty7 Ssl+ 0:07 \_ /usr/bin/X -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 vt7 -novtswitch

But X not actually listen any tcp port:

sudo netstat -Wpnatu
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 645/cupsd
tcp 0 0 192.168.1.110:55524 192.168.1.2:22 ESTABLISHED 4016/slogin
tcp 0 0 192.168.1.110:1008 192.168.1.2:2049 ESTABLISHED -
tcp6 0 0 ::1:631 :::* LISTEN 645/cupsd
tcp6 1 0 ::1:57617 ::1:631 CLOSE_WAIT 2955/indicator-prin
tcp6 1 0 ::1:57413 ::1:631 CLOSE_WAIT 782/cups-browsed
tcp6 1 0 ::1:57412 ::1:631 CLOSE_WAIT 782/cups-browsed
udp 0 0 0.0.0.0:32586 0.0.0.0:* 790/dhclient
udp 0 0 0.0.0.0:68 0.0.0.0:* 790/dhclient
udp 0 0 0.0.0.0:631 0.0.0.0:* 782/cups-browsed
udp 0 0 0.0.0.0:5353 0.0.0.0:* 663/avahi-daemon: r
udp 0 0 0.0.0.0:44534 0.0.0.0:* 663/avahi-daemon: r
udp6 0 0 :::40820 :::* 663/avahi-daemon: r
udp6 0 0 :::54127 :::* 790/dhclient
udp6 0 0 :::5353 :::* 663/avahi-daemon: r

So, what else i must to do?

UPD:

With Xorg 1.17 and later, -nolisten tcp is the default, and you need to explicitly state -listen tcp to enable tcp connections.

According this comment by alanc, i try add another line to lightdm.conf:

xserver-command=X -listen tcp

Finally all work as expected. My result lightdm.conf:

[Seat:*]
autologin-guest=false
autologin-user=ubuntu
autologin-user-timeout=0
autologin-session=lightdm-autologin
xserver-allow-tcp=true
xserver-command=X -listen tcp

And it's completely solved my problem.

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1 Answer

With Xorg 1.17 and later, -nolisten tcp is the default, and you need to explicitly state -listen tcp to enable tcp connections.

3