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Archiv für 'Cheatcodes'

Presenting the “Grandma Mode”

Friday, July 30th, 2010

Do you also have some relatives that always ask for “family support”: When you come to their house, you find a totally f***ed up Windows XP machine with tons of spyware and you’ll get to hear “I did not do anything”. The worst part of it: While you do the work, they keep talking at you.

Well it can be easier. Just configure your DSL router to forward inbound traffic on port 5500 to your desktop machine and get a nice DynDNS hostname. Then remaster any LessLinux Search and Rescue CD to include one boot entry that does not disable earlynet and add the cheatcode

        xvnc=|reverse|1280x800|24|my.dyndns.name|

In case of emergency tell your grandma to boot the CD with the respective entry. The earlynet script requests an IP address on all wired interfaces and instead of starting a local Xserver Xvnc is started and a reverse connection to your host is made where a listening VNC viewer must be running.

There is one drawback: the data is transmitted unencrypted, which might be an issue with sensitive data. You might however use this first VNC connection to build up a SSH tunnel between two hosts.

The background of this feature: I got some customers quite far away from here. With this cheatcode I can help them no matter where they are – no special configuration of their router required. This feature also will work over WLAN soon. I just introduced some cheatcodes to attach to a wireless network while startup. Those are not tested yet, so please be patient for a few more days.

Should work in all builds higher than 20100701-000000.

Netbooting LessLinux: NFS support

Monday, July 26th, 2010

After adding support for netbooting LessLinux by downloading the ISO image via HTTP/FTP I can announce support for NFS boot. For this feature you just need to add

        nfs=192.168.1.1:/dir/containing/iso

In this case, the NFS share is mounted read only (and no locking takes place), then all ISO files down to depth 2 are searched, loop back mounted and scanned for the proper version.txt. If the system is found, the settings for toram=value take place. In reasonable fast networks you should keep this threshold low, then the start of a program via network is quick, on networks with bad latencies you might set a low threshold to copy the entire system to RAM during startup.

You might download the ISO and the sources here:

To build yourself follow the instructions in those two articles: Build stage 01 and 02 and Build stage03.

Booting LessLinux via network

Monday, May 31st, 2010

As mentioned previously, support for netbooting LessLinux was recently introduced. In builds from 20100528-000000 it works stable and can be used in production environments. So please test the new function with this build:

Currently for netbooting a DHCP and PXE server are required, a HTTP daemon should be present, although it is possible to load the ISO directly from download.lesslinux.org. For now the ISO is completely stored in volatile memory — future versions will probably also allow NFS access. To load an ISO via HTTP just one additional parameter is necessary: (more…)

Accessing LessLinux with VNC

Thursday, May 27th, 2010

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

(more…)