distributed dhcp

[krock923]

hey, I posted this on another forum and didn't get a reply. maybe you guys can help. . .

Hi there, I'm working on trying to come up with a new dhcp solution for my school. Currently, there exists one central dhcp server and in each wiring closet, a browser that boots over the network with two network cards in it. One connected to the browsers vlan, and one connected to whatever vlan the machines that come into the closet are (usually dorms or classrooms).

What I'd like to do, but have no idea how is this: Upon bootup over the network, have the browser download a list of addresses it is responsible for and then only contact the master server if a new machine is connected or when the data expires. I assume that the database the browser downloads would have a TTL. this way, any short term problems with the main dhcp server won't cause a blowup of dhcp network wide which is what happens now, I think.

Any information related to this topic would be extremely helpful.

Thanks,
Matt

 

[ShackDaddy]

I don't understand exactly what this browser is. Is it a DHCP relay agent of sorts?

The easiest thing would be to just use two DHCP servers with overlapping scopes (superscopes) that would handle the same set of clients and provide redundancy for you if either went down.

Seems like way too much work to configure some sort of replication of the DHCP database to another system that is essentially a backup DHCP server. If you have a 4-day lease time, the only problems you will have with one server, if there is a four-hour outage, would be with client systems that have been turned off for more than 4 days and were brought online during the time of the outage.

What I'm trying to say is that lease-times themselves are a helpful tool for keeping things stable in the event of outages. The next tool in your pocket would be another DHCP server. Serving out DHCP requests is not that resource intensive, unless your lease time is incredibly short, so you should be able to find another server in your network to wear that hat.

I think the reason you haven't gotten responses to this question is because you seem to be asking for help implementing a solution that no one understands. There is all sorts of help available for your actual problem.

ShackDaddy