Saturday, and we are doing a little more training with 6 people. Some simple exercises to teach these guys how to determine if a mesh link is OK. We are starting with people who worked through the introductory course last Monday.
The entire course can be abbreviated to:
Applications -> Accesories -> terminal
# sudo su -
# /etc/init.d/network-manager stop
# ifconfig eth0 10.30.1.20
# ifconfig eth0
# ssh 10.30.1.1
# ping 10.130.1.10
# ping 10.130.1.10 -s 1400
# ping 10.130.1.12
# ping 10.130.1.12 -s 1400
The 10.130.1.10 node had a good link, the 10.130.1.12 node was marginal. The long pings (-s 1400) showed up the bad link. The 10.130.1.1 node is the Supernode. They logged into that first and ran the ping tests from there.
The Ubuntu network-manager can be a trap, it messes up your eth0 interface when it attempts to get an IP via dhcp. So I showed them how to switch network-manager off, however I imagine that line is just Linux-magic to them.
Coming from a developing world Windows background, it is hard to understand that a little white box 30m in the air can have a command line interface you can ssh into. For that matter it’s hard to understand ssh, or ifconfig, or a command line interface.
One pair of students stood out – a Cambodian sys-admin who is here helping out with the Univeristy Windows network, and his friend who (I think) was a Timorese Univeristy student with excellent English. They meticulously wrote every step down, then they took turns repeating the exercises multiple times.
Great to see such enthusiasm from people who have never used a Linux command line before. Such hunger to learn. If any of you want an adventure, these people will happily attend any IT course you can teach over here. Basic networking, database, web, anything would really help these guys get off the ground floor.
Ahh yes, nearly forgot to mention the network. We didn’t get close to my 24 hour uptime target. As I emerged from my hotel I saw the Blind Society node has spun around 180 degrees in the night! The boys fixed that fairly quickly. At about noon I noticed the batman scores wildly fluctuating and the ping performance had dropped. So I strolled around to the Blind Society to find the Nanostation again pointing a bit off path but also swaying nicely in the wind. The pole is fixed to the tree half way up and so moves with the wind! DOH! Probably OK for an omni but no good for a directional Nanostation.
After 7 days here strapping poles to trees is starting to seem normal to me.
The University node is only about 50m away and has a proper mast (with guy wires even) so we moved the Nanostation to there, leaving just the Mesh Potato on the Blind Society pole. Now we have received signal strengths of -45dBm between the Nanostations! At night they are glowing a dull red colour.
However still not a perfect link to the Blind Society MP, so I suspect lots of other Wifi in that area. I can see quite a few 8dB type omnis sticking up within a few 100m of that site.