Cisco DHCP Routing 1

[darren77uk]

Hi,

I am trying to connect two sites together(HQ + remote).

Currently there is a BDC at the remote site and I wish to allow the remote users to pick the DHCP from the HQ site using the router and not the BDC which is to be removed.

This is going to aid the use of Terminal Server.

I was told that you can use a IPHelper Command, is this correct and do I need it? If anyone can help me in setting this up, it would be much appreciated.

Cheers.
Darren

 

[axvpaa]

hi

http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t1/easyip2.htm

http://routergod.com/trinity/

http://routergod.com/hanktheangrydrunkendwarf/

hth
alex

 

[wybnormal]

If you are using the router to provide the DHCP, then a quick answer is you do not need IP helper. But, if you want to browse the network or provide any type of windows connectivity aside from pure IP, then you need the IP helper to move the netbios requests(SMB, WINS etc) (ports 137,138 and 139 are common) back and forth. DNS uses UDP port 53 so you may need to provide that too. You can selectively enable ports in order to isolate the DHCP traffic if that is what you want. That would be IP forwarding instead of IP helper.

Cisco has a nice paper on intergrating Cisco with Microsoft.

Windows Networking Design Implementation Guide

http://www.cisco.com/warp/public/473/winnt_dg.htm

MikeS Find me at

http://www.packetattack.com

"The trouble with giving up civil rights is that you never get them back"

 

[jeter]

You need to setup a ip-helper address at the remote site. if you do not it will cause troubles. Jeter@LasVegas.com
J.Fisher CCNA

 

[okanyilmaz]

tnx avpaa ur urls are quiet useful

the masters (wybnormal,jeter,avpaa) said the exact words but all i know is ip helper address command is used in order to implement a dhcp relay on a router. it will receive dhcp packets from the dhcp server.

u can watch the progress by debug ip dhcp server command on each side

 

[darren77uk]

Basically I need help on assigning this ip helper-address command at the config t level.

Can anyone assist me on this? I am still having problems in trying to configure this.

Cheers

 

[wybnormal]

You need to have IP helper on both ends.. also, you can either direct IP helper to a specific DHCP server(or whatever) OR do a directed broadcast.. ie.. 192.168.1.10 is a specific IP and 192.168.1.255 is a directed IP address.

!
interface Ethernet0
ip address 192.168.50.1 255.255.255.0
ip helper-address 192.1.1.255
no ip directed-broadcast
ip nat inside
no cdp enable
!

MikeS Find me at

http://www.packetattack.com

"The trouble with giving up civil rights is that you never get them back"

 

[darren77uk]

Excellent folks, thank you for your help. I managed to resolve my DHCP issue. I set scopes for the remote sites and used the IP Helper command to route the traffic.

It seems to work fine.

Thanks all.