ISC DHCP Question

Posted on 2004-11-28
Medium Priority
Last Modified: 2012-05-05
Is it possible to configure ISC DHCP Server v3 to listen to a specific interface even though the IP of the interface does not match the subnet range for the clients.

Eg. server IP: Serving clients with IP range ->
Question by:perola
  • 2
LVL 40

Accepted Solution

jlevie earned 200 total points
ID: 12692096
Yes, you can bind dhcpd to an interface(s). But a case where the subnet attached to an interface is different from the subnet the interface is configured for makes no sense.

I'd presume that your network topology has a router or firewall in between. In which case you need a DHCP relay agent running on the router/firewall and a subnet declaration for the -> subnet on the DHCP server.

Author Comment

ID: 12694316
Yes, we have a Cisco router (relay agent) that relays all DHCP traffic to a specific port (in this case the port where the DHCP Server is located),  this DHCP server is supposed to serve miltiple subnets with IP-addresses using Option-82. And we do not want to set an IP-addess on the DHCP Servers interface for each subnet.

But what do I write in the dhcpd.conf to bind all DHCP to one interface reguardless from the interface IP.

Expert Comment

ID: 12695715
Just start it with the interface you want it to bind to as parameter. For example: dhcpd eth0.
LVL 40

Expert Comment

ID: 12698201
In that case simply binding the DHCP server to the interface(s) that it should server requests on and creating subnet declarations for each of the subnets is all that's necessary. The DHCP relay agent does all the magic about routing the reply back to the client.

Featured Post

Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I have seen several blogs and forum entries elsewhere state that because NTFS volumes do not support linux ownership or permissions, they cannot be used for anonymous ftp upload through the vsftpd program.   IT can be done and here's how to get i…
Note: for this to work properly you need to use a Cross-Over network cable. 1. Connect both servers S1 and S2 on the second network slots respectively. Note that you can use the 1st slots but usually these would be occupied by the Service Provide…
If you're a developer or IT admin, you’re probably tasked with managing multiple websites, servers, applications, and levels of security on a daily basis. While this can be extremely time consuming, it can also be frustrating when systems aren't wor…
When cloud platforms entered the scene, users and companies jumped on board to take advantage of the many benefits, like the ability to work and connect with company information from various locations. What many didn't foresee was the increased risk…
Suggested Courses

807 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question