ip dhcp address

[lcucchetti]

I'm using "ip dhcp address" command to obtain an Ip address from dhcp server. It don't work.

I'm Using 12.2.12a , if I perform "debug dhcp detail" I obtain this output :

DHCP: SDiscover: sending 282 byte length DHCP packet

DHCP: SDiscover 282 bytes

B'cast on Ethernet0/0 interface from 0.0.0.0

DHCP: Received a BOOTREP pkt

DHCP: Scan: Message type: DHCP Offer

DHCP: Scan: Subnet Address Option: 255.255.248.0

DHCP: Scan: Server ID Option: xx.yy.zz.kk

DHCP: Scan: Router Option: xx.yy.zz.1

DHCP: Scan: DNS Name Server Option: a.b.c.d

DHCP: Scan: bad Security Server Option len 19

DHCP: Error in pkt. punting

I think the problem is in "bad Security Server Option len 19"

but I don't know what is it and I think not exist "security option"

in dhcp option.

notice all windows 95 dhcp client connected on the same lan work fine

there is no information on cisco site.. to debug dhcp detail

someone can help me ???

thanks

Lorenzo

[prafuljaded]

If you are using a single lan and all other machines are able to reach DHCP server, the problem may be with the pc.

which switch are u using? have u configured vlans on switch???

Let us know...

[lcucchetti]

I'm using dhcp client configuration to obtain an Internet Ip address from my ISP.

I have one switch connect to my ISP by Gigabit ethernet. My ISP had configurend only one port on switch.

So.. if I connect windows 95 dhcp client on switch.. it obtain all IP configuration and it work fine.

Now... instead of pc I would like to use an 2600 router (with nat configuration, so all my network can surf on internet), I had configured "ip address dhcp" but it don't work.

I had perform "debug dhcp detail" the result I had put in my first message.

I don't know how is configured ISP switch but I think that if a PC can obtain IP address by dhcp, the router have to obtain too.

I tryed to change varied IOS but the result is the same

thanks

bye

Lorenzo

[prafuljaded]

Now that U want to replace PC with A router, U need to configure

"ip address negotiated" on ur WAN Interface or any interface U connect to ISP so that it gets IP address from ISP.

Chk this out:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/dial_c/dcezip.htm

Hope this helps....

[lcucchetti]

with "ip address negotiated" I obtain an Ip address by PPP

I have to obtain it by DHCP client on ethernet interface.

I used "ip dhcp address" but it don't work

thank

bye

Lorenzo

[chet.myrick]

OK, I don't pretend to be a CISCO expert but this is what I have found:

1. I assume you mis-typed the command to set the interface to use DHCP. It is "ip address dhcp" . Since "ip dhcp address" isn't a valid command, the router would have objected.

2. If not, go to the outside interface and use the right command.

3. Since you are using DHCP, I also assume you are using a high-speed modem of some sort to connect to your ISP. I found that you must turn-off your modem for about 30 seconds and with your router off, turn it back on. After the modem cycles, turn the router on. It appears the mac address of the modem gets tied to the first device's mac address (in this case your Micro$oft box) and won't let go.

4. Subsequent reloads of the router won't require this because it now knows the mac address of the routher. If you go back to the Micro$oft box then do the power-off thing again.

5. Now, if someone can help me set NAT to work with the DHCP client I will be happy. Seems NAT wants an IP or group of IPs to work.

Chet

[bcbvale]

You can configure NAT to use an interface instead of an ip range. That will allow you to use the DHCP interface address as your global address.

Check this link for an example of a cisco router behind a cable modem.

http://www.cisco.com/warp/public/109/router_behind_cm_19268.shtml

ChrisV

[chet.myrick]

Thanks, ChrisV. I actually figured it out shortly after sending the msg. Put a C2514 on the home network with IPCOP firewall behind the router. Got tired of all the junk being logged on the firewall.

Chet