Teamviewer : procédure pour l’utilisateur

Teamviewer est un logiciel de prise en main à distance : il permet à un tiers de se connecter à votre ordinateur (pour effectuer des opérations de maintenance, ou vous aider à effectuer une tâche).

Voici la procédure pour lancer Teamviewer sur votre machine, et inviter un ami à s’y connecter.

Note pour les admins : Teamviewer offre maintenant un client spontané, qui permet de lancer le programme avec un minimum de clics.

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Device Mapper : une explication simple

Le Device Mapper (ou Carte/Correspondance des périphériques en français) permet de créer un périphérique block (un « disque dur »…) à partir d’autres périphériques blocks. 

En d’autres termes, dans l’utilisation la plus simple, vous pouvez utiliser  des morceaux de partitions de plusieurs disques, pour créer un disque composite.

C’est utilisé surtout avec le LVM et le RAID logiciel.

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What is a Layer 3 switch really?

Depending on who you ask, the answer will be different. It seems everyone has an opinion about what a Layer 3 switch is. I have my own personal definition, which is based on the OSI model.

Also, some definitions really beat around the bush. All of this creates confusion in the mind of newbies people concerned and clearly, when you try to make it clear, the answer is not simple, although specialists usually manage to get out of it without too much trouble.

Let’s see what are different definitions we find of Layer 3 switching on the Internet. Continue reading

[IPv6] How 6to4 works : from your 2002::/16 LAN to the IPv6 Internet

Last article about 6to4 explained how your 6to4, ie 2002::16 network is reached from the IPv6 internet. Good news is that it was the hardest part to explain and understand.

Still, the question remains : when you decide to send packets to the IPv6 Internet through the IPv4 Internet with 6to4, how does your gateway do? Continue reading

RIP timers and reality, #3 (HOLDDOWN again)

We’re now going to test a different topology introduced at the end of article #2.

We are now going to test the HOLDDOWN timer of RIP when the backup router send a route with a metric higher than the primary router.

In this series of tests, we’ll see if the HOLDDOWN works in case the route disappears of R100 because of HOLDDOWN timer. Next time, we’ll see if it disappear if R101 advertises a metric 16 for NETWORK.

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