monitor unreacheble routes installed by babel

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Readme.md

rmon

rmon monitors unreachable routes installed by babeld.

Does not need any special permissions to run.

howto

install & run

$ git clone https://git.freifunk-franken.de/lemmi/rmon
$ cd rmon
$ go get -v
$ go run .

open webbrowser

http://localhost:8080/

Note

babeld can spew out massive amounts of route changes that can fill the netlink socket. rmon tries to allocate a 16MB receive buffer, which seems to be enough for the moment. For this to work check /proc/sys/net/core/rmem_max to be more than 16MB (16777216).

Set receive buffer size temporarily

Do one of the following:

# echo 16777216 > /proc/sys/net/core/rmem_max

# sysctl -w net.core.rmem_max=16777216

Set receive buffer pemanently

Add the following line to /etc/sysctl.conf:

net.core.rmem_max = 16777216

and run

# sysctl -p