Multipe DHCP Servers

[lanjoe]

I have a DHCP serving running on my 192.168.100.x network, and another DHCP server running on my 192.168.200.x network.

If the 100.x server goes down, my 100.x clients receive an IP address from the 200.x DHCP server.

Is there a way to prevent this from happening?


Thanks.

 

[MattWray]

You either have a DHCP relay agent or your router has the DHCP Helper turned on. DHCP requests will not pass a router unless there is something forwarding them on....

Thanks,

Matt Wray
MCSE, MCSA, MCP, CCNA

http://www.sss-steel.com

 

[GlenJohnson]

You should always create superscopes when dealing with multiple dhcp servers on the same network. One scope for each server, have both of them in the superscope so that they are aware of each other, and exclude them from each other. (Superscope would have address' of 192.168.100.x through 200.x. Individual scopes would be for the 100 and 200 scopes. Exclude the 200.x from the 100.x and exclude the 100.x from the 200.x.) Good luck.

Glen A. Johnson
Johnson Computer Consulting

http://www.johnsoncomputers.us

"I only know that I know nothing."
Socrates (47-399 BC); Greek philosopher

Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884

 

[ricpinto]

To prevent this from happening, follow Mattwray suggestion. Turn Off the DHCP relay agent/IP helper on the router. But why prevent this from happening, just configure it properly so it will hands out the correct IP address when one DHCP is down. On both DHCP server create a superscope or create 2 scope for each network (subnet). The DCHP will know which range of IP address it will offer by referring to DHCP relay agent.