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At barcamp kerala 7

December 23rd, 2009

I took a session on recycling old PCs with LTSP at   barcamp kerala 7 last Sunday.  Even though I am associated  with the organizers of barcamp ever since its inception in Kerala, I could not attend any of the previous ones due to various reasons. So I was a bit skeptical about the kind of people I may meet. Also, this was the first public lecture I gave after assuming charges of Principal College of Engineering Attingal. I  conveniently hid this fact from the audience suspecting that my job profile might overshadow the geek in me.

ltsp
I was picked up from home by Kenney Jacob at 5.30 am  and we stated our journey to Changannasery on a TATA VISTA . The car was fantastic with GPS can other gizmos . A few of Kenney’s colleagues were also present in the car. We reached the  venue around 8.45 to find that the  gates of the Krishtu Jayanti college were closed. Kenny made some frantic telephone calls and finally we were asked to enter the college via  the  gates of a Catholic church.

There were around  70 guys in the hall. There was some initial hiccups and the  sessions took some time to start . I missed introductory remark by Kevin as I went to the nearest tea shop for a quick dose of coffee. The next session from Prassed Pai on 3d graphics programming was good and reminded me of my PG classes at CUSAT where we did all the shading and drawing algorithms. I think most of the audience was clue less about the topic.
The next session    Building Complex Website the Drupal Way from  Fredrik Jonsson? was   enlightening.
The third  session on Media by Kenney Jacob initiated some interesting discussions among the audience. Some of the participants expressed the fears about corporate media  manipulating facts .
Next was a cake cutting session . Some one suggested Fredrik Jonsson’s name for the event and every one clapped  when he cut the big cake sponsored by   ayruz web holdings  . Later I had lunch at a local teashop .
I took the first session in the after noon. My Idea was to set up my laptop as ltsp server and net book as the client . Then project the client to  the  big screen and start the presentation on the client.
The Sharp projector  at the venue was behaving erratically. It showed only half of the screen. I had to change instantly to the white board and start writing.  I briefly explained the  LTSP  with a figure that I drew and later on moved the projector to my laptop. The presentation was shown after explaining things with a white board.  I think half of the audience got confused by then.
The next session from UST global was  quite boring. I think such PR crap should be avoided in barcamps. I missed the session by Binny VA as I went out for a tea again.

The last session on linux devices was good,  but Praseed Pai  seemed to be the only person understanding it.
Finally, Fr. Abraham Mulamootil made a surprise appearance. I think it is the first time a catholic priest is seen publicly in a bar(camp). Any way he seems to be the only geek in the church.
The entire event was wound up around 6pm.
The facilities at the venue were pathetic.  No one from the college turned up. There was no net connectivity.  The wifi link of the college was running but their firewall was preventing outgoing net  request. Hope the next barcamp at Thiruvalla will be better and more interesting.

vu2swx Computers, Gnu/Linux

Pidgin unable to connect to yahoo

June 21st, 2009

I am using pidgin as  chat client for both yahoo and gtalk. Recently, yahoo has stopped support for older versions of their own yahoo messenger clients. ( anything less than version 7.5  fails ) . It also means that most of the third party clients such as pidgin has  problems  in login.

On my ubuntu 9.04, the default  pidgin version is  2.5.5.   You can work around the yahoo login problem  as shown below.

Open Accounts-> Manage accounts.

Click on the account you want to  fix

Click on modify.

Click on advanced tab.

The pager server is set to  scs.msg.yahoo.com

Change it to    cs101.msg.mud.yahoo.com

Click on Save

Restart  pidgin

It seems yahoo is  rolling out a new authentication protocol. Let us wait for  a new pidgin  update

Update:

Pidgin 2.5.7 which fixes the yahoo login problem is out. You can install it as given below.

Import the  public key  for Launchpad PPA for Pidgin Developers

$ sudo apt-key adv –recv-keys –keyserver keyserver.ubuntu.com \     67265eb522bdd6b1c69e66ed7fb8bee0a1f196a8

Add the following lines to /etc/apt/sources.list

deb http://ppa.launchpad.net/pidgin-developers/ppa/ubuntu   jaunty main

Run apt-get update and apt-get install pidgin.

The PPA contains new pidgin releases for other versions of ubuntu (  dapper gutsy, hardy ,intrepid and karmic) You can just replace jaunty in sources.list line indicating this ppa with you distro and enjoy yahoo messenger on pidgin.

vu2swx Gnu/Linux ,

Blogging with scribefire

June 16th, 2009

Scribefire  is a cool firefox add on which a  blogger cannot miss   Using this  firefox add-on, you can blog with out leaving your browser.   Installation is simple. Browse to this page Just click on the addto firefox button and restart firefox.

firefox with scribefire

You can start scribefire  by clicking on the scribefire icon. It will open up scribefire as shown below.

Now, you can set up a blog account from the blogs menu and start enjoying scribefire. It supports several features such as notifying various blog aggregations services , ftp uploads etc. Have a look at the features.

Scribefire startup screen

Scribefire startup screen

vu2swx Gnu/Linux , , ,

Disabling the new notification system in Ubuntu 9.04

May 13th, 2009

volume

The  notification system in the newly released ubuntu 9.04 ( Jaunty)  uses the notify-osd framework.  This system provides a standard way of  doing passive pop up notification on the  desktop.The notifications are semi transparent click through  bubbles.  These pop ups will disappear after  a short period of time.  Some  times  these bubbles    can be irritating.

You can disable the  notifications with the following command.

mv /usr/share/dbus-1/services/org.freedesktop.Notifications.service /usr/share/dbus-1/services/org.freedesktop.Notifications.service.disabled

( You have to restart X )

You can switch back to the original gnome-style  notification system  by installing the package named  gnome-stracciatella-session. Also ,  have a look at this blog.

# apt-get install gnome-stracciatella-session

vu2swx Gnu/Linux

Installing LTSP on Ubuntu 9.04

May 11th, 2009

Installing LTSP and enabling thin clients to boot from your ubuntu 9.04 machine is very  easy.

I did the following steps.

a) Install ubuntu 9.04   ( aka Jaunty) desktop   with a static IP.    (  A static IP is needed as your ubuntu box is going to act as a server. My IP is 192.168.0.1). Set up Internet access on this machine. You need to download a lot of packages  from the net to complete the installation.

b)  Install  the packages  ltsp-server-standalone and openssh-server

# apt-get install ltsp-server-standalone
# apt-get install openssh-server

c)  Build the LTSP client environment.

#ltsp-build-client

This  command will download all the necessary packages from Internet and build  your environment.

Have a look at /opt/ltsp/i386. This directory will  now contain the chroot environment for the thin clients.  If you want to tweak any settings  you cna do it here.

d) Edit the  /etc/ltsp/dhcpd.conf to suit your network setting. This file  will serve  the ip range  192.168.0.20 192.168.0.250 by default. If your network uses this range you can leave it  as it is. (The default file worked for me as my server IP is 192.168.0.1)

e) Run the following commands.

#ltsp-update-sshkeys

#ltsp-update-image

The first  command above will export the ssh keys of the server  to the ltsp client environment. The  ltsp-update-image command will rebuild a squashfs image from the ltsp chroot environment and place it under /opt/ltsp/images directory.  This image will be exported to the thin client as root file system by the NBD daemon on the server.

Your LTSP server is ready.  Try booting form a client via pxe or etherboot. You can also try to boot the thin client in qemulator.
There is a sample script for this in /usr/share/doc/ltsp-server/examples/ named qemu-ltsp.

Note:    If you change any thing under /opt/ltsp/i386 , you must rebuild the image for the change to be reflected on the client. Also, if you change the IP address of the server you must do an ltsp-update-sshkeys followed by  ltsp-update-image.

vu2swx Computers, Gnu/Linux, Living in India, Uncategorized , ,