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Accessing LessLinux with VNC

As I mentioned before, “LessLinux Search and Rescue” is intended to be a versatile live system for typical service jobs that have to be done in mixed environments. To make work easier, a service system should be net-bootable and accessible with a remote desktop application. In builds starting with timestamps after 20100526-000000 I included support for both functions:

  • Booting the kernel and initramfs with PXE and loading the system ISO with wget by http or ftp
  • Starting the desktop with Xvnc instead a local X server

Currently both functions just work with a wired network interface. This post covers VNC access, I will write on PXE booting later.

To test VNC access, download the latest build:

…or build it yourself according to the last two articles withe those buildscripts and overlays (in this case the extra switch -u for unstable is necessary):

Doing it the easy way

In trusted networks, you may start Xvnc on the external interface, this means VNC access is granted without password. Just press the Tab key in the boot menu and add

        xvnc=|remote|1280x800|24|

The first value tells Xvnc to bind to the external interface, the second is the screen resolution to use (any value is accepted here), and the third parameter is the color depth. On congested networks you might reduce the depth to 16. It also makes sense to add runtimeconf to the list skipservices. When finished booting, you can connect on port 5900.

Doing it the secure way

Specifying

        xvnc=|local|1280x800|24|

tells Xvnc to bind to 127.0.0.1. So no external connections are allowed. To access, you must tunnel port 5900 over SSH. To make this possible, first remove ssh and roothash from the list skipservices, then add a roothash by specifying:

        rootpwhash=$1$ILXt/Dc3$DmYp.51WCDNjGuTL90eju/

This is the MD5 hash for the simple password test. I created this Hash with the command openssl passwd -1, Apaches htpasswd might also work. Then after the system is fully booted, you can first connect with SSH and use -L to forward :

        ssh -L 5900:localhost:5900 root@192.168.1.23

Now VNC is available on port 5900 on you local machine, simply connect this way:

        vncviewer localhost:0

The current build also is the first one to use kernel 2.6.34 and it introduces libraries from Gnome 2.30. So please test and give me feedback!

Eine Antwort auf “Accessing LessLinux with VNC”

  1. Das Rootserver-Experiment » Blog Archive » Status-Update LessLinux (July 23rd, 2011 um 8:00 pm)

    [...] Zugriff per VNC: Per Cheatcode kann nun angegeben werden, statt einer lokalen Grafikkarte einen VNC-Server anzusteuern. Das klappt offen fürs ganze Netz oder auf localhost für unsichere Umgebungen Weiter im LessLinux-Blog [...]