Re: [OT] 2 dhcp server on same lan

[Eike Lantzsch <zp6cge@gmx.net>]

On Thursday 21 May 2015 15:33:09 Bob Proulx wrote:
> Pol Hallen wrote:
> > On same network 192.168.1.0/24 I can put 2 AP with each one own dhcp
> > server? (obviously with different range but on same network).
> > 
> > router IP 192.168.1.1
> > AP1 IP 192.168.1.2 (dhcp 192.168.100-149)
> > AP2 IP 192.168.1.3 (dhcp 192.168.150-199)
> 
> What is the purpose for doing such a configuration?  All answers
> depend upon the purpose because it all depends.
> 
> For example the above does NOT provide for high availability.  And I
> can't think of any other reason for it.  And even then it depends upon
> the implementation of the dhcp server.  I would think that the little
> blue consumer boxes would not work sufficiently but again it depends.
> 
> Bob

DHCP failover on a small network does not seem to be worth the effort, except 
for training purposes. Exactly that is why this thread was very informative 
for me. Just for kicks (training) I was trying for a while to set up two dhcp 
servers on my network. One OpenBSD on a router and the other on Debian arm 
isc-dhcp-server on a cubietruck.
One sends sync messages and the other connects to ip-ports - duh!
The philosophy of OpenBSD dhcp seems to be really wide area networks not being 
on the same premises and isc-dhcp seems to be better fitted for LAN.
Now I know that my endeavours are futile. The synchronization between two 
OpenBSD dhcp servers and the failover isc-dhcp-server are essentially different 
and do not work together. Either 2 * isc-dhcp-server (which is available for 
OpenBSD as a package) or 2 * OpenBSD dhcp servers (which does not exist for 
the armv7l cubietruck) => need another machine or "maquinita".

So as for the OP having only small commercial SoHo routers there is no route 
to success either.

Your posts made me dig deeper into the matter and I learned a lot.
Thanks to Pol for bringing the subject up.
Thanks to Darac, Erwan and Bob for giving advice.

Cheers
Eike