[Babel-users] Ahcpd update in OpenWrt (quick HOWTO)

[Gabriel Kerneis]

On Mon, May 31, 2010 at 11:41:43PM +0200, Mitar wrote:
> OK. But what is then difference with running a dnsmasq on every node
> with DHCP where every node has its own IPv4 pool for clients? dnsmasq
> does not yet support IPv6 but is this then the only difference?

Off the the top of my head:
- IPv6 support,
- no need to have a server on every node (although some redundancy is
  welcomed), which makes IPv4 configuration easier (fewer sub-ranges to
  configure),
- guaranteed to work in any topology of your mesh network provided you
  have at list one server in your connected set (dhcp was NOT designed
  to work reliably on mesh networks, AFAIK).

What I might have forgotten to mention is that, of course, ahcp clients
also act as forwarders.

Think of the following situation:
(Internet) ---- A ---- B ---- C
where A is your Internet gateway + ahcp server, and B and C are two
clients.  If C cannot reach A, dhcp would break but ahcp will behave
correctly.  This is a very common pattern in my experience: you discover
that some part of your lab is not covered by your mesh network, just
take another Fonera, flash it with a customized image (featuring
babel and ahcpd in client mode), plug it near the dead zone, and it
works!

Now, there are two downsides:
- you have to install ahcp (whereas every decent has a dhcp client
  bundled),
- no Windows port exists yet.

Regards,
-- 
Gabriel