[CentOS] Centos 7 dhcpd failure to allow a 2nd network over same interal nic

Sun Jan 15 17:11:55 UTC 2017
Gregory P. Ennis <PoMec at PoMec.net>

Date: Sun, 15 Jan 2017 11:57:35 -0500

> I have not been able to make any headway resolving this problem; 

Personally, I don't understand how you expect the DHCP server to decide
which scope to use when a new connection appears on the network.

DHCP discovery queries are presented from to, not to
a particular network's broadcast address.

I'd be interested to see what happens when one of your 10.x.x.x nodes
reaches half time or lease expiration and tries to renew its IP.  I tend to
think it would then be offered an address from the 192.168.0.x scope
instead, if it's currently offering those to the wireless connections.

Thanks for your response !!!!

All I can say is that when I looked at the dhcpd.conf examples and read
the man pages as well as the explanations of how dhcpd works, we should
be able to use dhcpd for more than one subnet :

Take a look at Rehat's explanation of a Multihomed dhcp server :


If I am reading this and other documents incorrectly, then I would
welcome having you step on my toes.  I have spent more time on time on
this problem than it would have taken just to purchase another nic card
and put in another piece of hardware.  However, it is always worth the
effort in learning how everything works.

Thanks again for your input!!!

Greg Ennis