BroadcastStorm

Category:Sasecurity
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We had same problem in one end of our mesh, try to set Transmit Power 
to AUTO on all your nodes, it solved the problem for us: iwconfig wlan0 
txpower auto To much signal is not the solution. After this I found that some nodes 
only needed -2 to +2 db outputpower (from the cards) to maintain a 11 Mbit 
link over 1 km!!BR
I'm getting the same thing. I have 5 nodes that dog leg around 18 
apartment buildings. The reflection from these building I though we giving me 
some weird reading. For example: 
Unit "D" can mesh with unit "A" but between them is 16 floors and 
concrete and metal. Basically no way no how the signal is going to penetrate 
that building but because of the other building in the area the signal is
bouncing around. Meshap reports that he can talk with the unit 
directly because of the signal strength but what it is getting is true noise. I
change the network to "blocknode" these signal in order for them to 
properly " dog leg" around the build. When "blocknode" is working Reporter 
indicates that Unit "D" can see unit "A" via unit "C"
Then what happens is Meshap does an automatic unblock node (even when 
Wiana setting is set to disable) I assume it is call broadunblock then all of 
a sudden the node start see the noisy environment and I start to loose 
units "A" and "C"
I can ping them ok and I can ssh into them. Remotemanagement fails and
people connected to these Meshap loose connectivity.
Too resolve the problem I reboot the Gateway nodes everyday. That 
seems to resolve the problem temporarily.
Next I start getting a Broadcast Storm. I'm not sure if this related 
but the outer nodes i.e. "A" and "C" start reporting Broadcast Storm.
I have been battling the network for weeks now. I have add some 200mW 
cards to increase sensitivity of Gateway but this only increased the problem.
I'm not sure if the software is buggy or the operators is nuts. I wish 
we had a bench mark or better understand of what how blocknode actually 
works and if it is really working. 
I noticed that to use the "walled garden" you have to use dev 88. 
What I will try to do is first reduce power on the 200 mW cards
Second if that doesn't work I will try to add blocknode in crontab 
every 10 minutes to stop the direct connections of the two nodes.
Third If that doesn't work I will try to do the reversal and set Wiana 
to unblock nodes every 10 minutes again.
Hopefully these combination may give me so clue to your and my 
problems.
Subject: RE: [MeshAPuser] help, Im going insane
Yes I can ssh into the node.. remember the node is not unreadable the 
172.16 tunnel is. That is what is so strange.
1.221.35.250 uses a tunnel called 172.16.244.2 BR
1.221.35.250 is reachable and I can login and all is fine.. BR
but 172.16.244.2 the tunnel that everyone uses for internet access is not
reachable 
Then a few minutes or seconds later it is reachable. This cause all
downloads to stop and restart which kills many internet sessions.
If both the mesh IP and the tunnel IP were unreachable, I would 
understand, but when you get great ping times to the mesh ppoint and get 
unreachable on the tunnel, it make me think something is happening to the tunnels.
All nodes are running dev88
Subject: RE: [MeshAPuser] help, Im going insane
Ken can you ssh into the unreachable nodes? Sound like a stupid 
question but what dev are you using?
Help please.. I need to understand why or how this is happening.. 
These 2 tunnels report unreachable BR
172.16.244.2 is unreachable BR
172.16.248.2 is unreachable BR
but the mesh point itself responds fine. BR
1.221.35.250 is alive (11.8 ms)------- 172.16.244.2 is unreachableBR
1.252.243.83 is alive (14.9 ms)------- 172.16.248.2 is unreachable BR
I have the gateway 'locked' to the proper gateway and I have blocked 
the other routes, so there is no other way to get out.
I was beginning to think this was a wifi problem unitl I noticed that a 
node further downstream is responding.. abit slow.. and its mesh ping time 
is also fine. BR
1.76.85.159 is alive (14.2 ms)----- 172.16.137.2 is alive (698 ms)BR
There is no relation to the amount of traffic that is one the network. 
This problem happens at 6am and 1am at 12noon at 6pm.. I monitor the 
traffic at the gateway through a MikroTik router so I can watch all traffic.. and 
there is not a lot of traffic When I look at the node they all seem fine.. they just don't respond. 
And then they do.. but the mesh ip always seems to respond.
People are now calling asking why it is bouncing.