[Olsr-users] AHCP

[Juliusz Chroboczek]

> someone send me a working configuration for ahcp and i can provide
> a working startup routine for ahcp in general, shouldnt matter the chip
> type.

Note that the current (version 1) AHCP protocol can only work in hybrid
IPv6/IPv4 networks, not in pure IPv4 networks.  I'm currently working on
version 2 of the protocol, which won't have this limitation, and while
I have a working prototype, it won't be ready for release before this
summer (lots of other stuff to do first).

But FWIW, here's how I configure our mesh network over here in Paris.

We've got three kind of nodes:

1. normal mesh nodes (intuitively, ``client nodes'')

These just run

    ahcpd -D -I /var/run/ahcpd.pid wlan0

and autoconfigure using AHCP.

2. authoritative AHCP nodes

These are able to give out IPv6, name server and NTP information to other
nodes.  They are configured by

    ahcpd -D -I /var/run/ahcpd.pid -c /var/lib/ahcp.config wlan0

where ahcpd.config was generated using

    ahcp-generate -P babel -p ... -n ... -N ... -s ... > ahcp.config

3. Stateful AHCP server

There's only one of these, and it gives out IPv4 configuration to nodes
that've already configured IPv6.  It's run as

   ahcpd -D -I /var/run/ahcpd.pid \
         -S 192.168.14.192 192.168.4.254 /var/lib/ahcpd-leases \
         wlan0

Two things to note:

1. it is possible to have single node run as both authoritative and
stateful, by specifying both -c and -S.

2. For redundancy, you may specify multiple stateful servers.  Make sure
that they serve disjoint address ranges.

Once again -- AHCP version 1 has a number of limitations, and is an overly
complex protocol.  I consider it as a failure.  You may want to wait until
I release version 2, which is much easier to use and doesn't require that
you run a hybrid network.

Regards,

                                        Juliusz