Full Circle Magazine FR

Last month, I wrote about the Linux Terminal Server Project (LTSP) installation I did for the Nuer Community Center here in Kitchener, Ontario, Canada. The center had just acquired space, but wanted some computers for members to play and do research on. LTSP seemed like a perfect fit for their needs: a low-cost (in this case donated) centrally managed system that you could hook up just about any other computer to and get the same experience. When I wrote last month’s article, the community center didn’t have an Internet connection yet. The center also had not officially opened yet, so there was no chance for feedback about what was working and what wasn’t. When I left last month, we’d set up 2 workstations, the server, a switch, and a router (that only connected to the switch). Members could play games, write documents, edit photographs, but because they didn’t have an Internet connection, there were a lot of things they couldn’t do. I knew that, when they added the Internet connection,it wouldn’t be a matter of just plugging it into the switch or router because the router I was using would conflict with the router built into whatever modem/router they got, and the server wouldn’t be set up with the correct range of I.P. addresses (in the /etc/dnsmasq.d/ltsp.conf file).

Le mois dernier, j'ai décrit l'installation du LTSP (projet Linux Terminal Server) que j'ai faite pour le Centre communautaire Nuer ici à Kitchener dans l'Ontario, au Canada. Le centre venait d'acquérir de la place, mais voulait quelques ordinateurs sur lesquels les membres pourraient jouer et faire des recherchers. Le LTSP semblait répondre à leur besoins de façon parfaite : un système à bas prix (dans ce cas, un don), géré de manière centralisée auquel vous pourriez brancher à peu près tout autre ordinateur et avoir la même expérience. Quand j'ai écrit l'article du mois dernier, le Centre n'avait pas encore de connexion au Net. En outre, le Centre n'était toujours pas ouvert officiellement et il n'y avait donc pas de possibilités de retours sur ce qui fonctionnait ou pas.

Quand je suis parti le mois dernier, nous avions configuré deux postes de travail, le serveur, un commutateur et un routeur (qui ne se connectait qu'au commutateur). Les membres pouvaient jouer, écrire des documents, retoucher des photos, …, mais, puisqu'il n'y avait pas de connexion Internet, il y avait beaucoup de choses qu'ils ne pouvaient pas faire. Je savais que, lors de l'ajout d'une connexion Internet, ce serait plus compliqué qu'un branchement tout simple au commutateur ou au routeur, parce que le routeur que j'avais utilisé serait en conflit avec le routeur intégré au modem/routeur qu'ils obtiendraient et le serveur ne serait pas configuré avec la plage correcte des adresses IP (dans le fichier /etc/dnsmasq.d/ltsp.conf).

In fact, the center ran into a problem even more simple than switching out the router, children hiding the username and password stickers I made. Here I was thinking about what problems I might run into when configuring the server for the new modem/router, when the real problems were much simpler: access to the machine. I printed off more stickers, and this time we stuck them to the bottom of the keyboards instead of at the base of the monitors. I could have set autologin for the clients, but at some point, if they add more clients, we might make each login a unique login (guest01, guest02). Because there are only a couple of machines, and the server has 8GB of RAM, one guest account is enough. Setting up the clients to work with the Internet connection wasn’t as difficult as I expected. The most difficult part was actually physically moving the workstations from one area to another. The Internet connection was set up in an area about 15 feet away from the workstations. We actually didn’t need to move the workstations closer because the ethernet cable I initially used to connect the server to the 10/100/1000 switch was about 25 feet long. I used the 25-foot ethernet cable to connect the Internet modem/switch to the gigabit switch, and all computers, including the server, also connected to the gigabit switch. The old router was set aside (no need for a second router since their modem had a built-in router).

When I set up the network initially, I didn’t want it conflicting with any routers we had at work. I chose the 192.168.80.x range. The new router defaulted to 192.168.1.x, so I needed to change this range in the /etc/dnsmasq.d/ltsp.conf file on the server (shown middle top). After changing the I.P. address it was necessary to update the ssh-keys and the image that gets deployed to the clients: sudo ltsp-update-sshkeys sudo ltsp-update-image sudo sed -i 's/ipappend 2/ipappend 3/g' /var/lib/tftpboot/ltsp/i386/pxelinux.cfg/default I made all these changes while the old router was still hooked up (under the 192.168.80.x address), so I worried that it might not work, but when I disconnected the old router and plugged the new modem/router into the switch, everything worked smoothly. I shut down the server and clients, but only because we had to move computers and furniture around. This likely would have worked without a reboot.

One important point to note is if the server gets rebooted/switched off, clients should be switched off/rebooted. The server should be the first to boot, otherwise your clients won’t be connected (they actually use the server resources). At this point, there still hasn’t been enough time and testing to say how well the installation works, but the community center seems determined to stay the course with LTSP and Ubuntu MATE. Special thanks to Peter, James, Chul and all the Nuer Community center members who were very welcoming and helpful with this and the last LTSP article. LTSP resources: LTSP home page: http://www.ltsp.org/ Ubuntu LTSP community help: https://help.ubuntu.com/community/UbuntuLTSP