dhcp and isdn

[ipothos]

i want to set up a cisco 1841 as a dhcp server and also to set up this router to use an isdn as the backup line when the serial wan link goes down...

can anyone send me a typicall configuration or where i can find information about this scenario??

 

[Jimtron26]

For DHCP

router#conf t
router(config)#service dhcp
router(config)#dhcp pool MYPOOL
router(config-dhcp)#network x.x.x.x
router(config)#ip dhcp excluded-address <start address> <end address>

Optional
router(config-dhcp)#default-router <gateway ip address>
router(config-dhcp)#dns-server <DNS server>
router(config-dhcp)#netbios-name-server <WINS server>
router(config-dhcp)#domain-name <Domain Name>

Hope this helps

Jim CCNA

 

[MDW19873]

For the DHCP I also recommend the "default-router" command so that the devices have a gateway. Otherwise it can be a mess.

For the backup link, I'll assume you have both your mainline and your back up link configured.

Assuming you're mainline is a serial interface:

interface serial0/0
backup interface [interface[slot/port]]
backup delay [seconds - link failure] [seconds - link resumed]

EXAMPLE:

interface serial0/0
backup interface dailer0
backup delay 5 10

Documentation:

http://www.cisco.com/warp/public/129/bri-back-dp.html

Good luck

A+, i-Net+, Network+, CCNA, CCNP