Configure DHCP on router and switch

[paquinjrm]

Good afternoon,

  I'm trying to configure DHCP using CLI on a 2610 router and 2950 switch.  With my present config, the host at the end of the switch (configured to receive ip via DHCP) is not getting anything assigned.  Here are some shows:

Router:

Router_1#show ip int br
Interface                  IP-Address         OK?   Method   Status                        Protocol
FastEthernet0/0       192.168.10.1      YES   manual    up                              up   (leading to switch)
Serial0/0                  unassigned         YES   unset      administratively down  down
Serial0/1                  unassigned         YES   unset      administratively down  down
Ethernet1/0              unassigned         YES   unset      administratively down  down
Ethernet1/1              unassigned         YES   unset      administratively down  down
Ethernet1/2              unassigned         YES   unset      administratively down  down
Ethernet1/3              unassigned         YES   unset      administratively down  down

Router_1#show ip dhcp pool

Pool acer_pool :
Utilization mark (high/low)   : 100 / 0
Subnet size (first/next)       : 0 / 0
Total addresses                : 254
Leased addresses            : 0
Pending event                   : none
1 subnet is currently in the pool :
Current index        IP address range                              Leased addresses
192.168.10.1       192.168.10.1     - 192.168.10.254                   0

Switch:

Switch_1#show ip int br
Interface                      IP-Address      OK?     Method      Status        Protocol
Vlan1                           unassigned      YES     NVRAM     up              up
FastEthernet0/1            unassigned      YES     unset         up             up      (leading to router)
FastEthernet0/2            unassigned      YES     unset         down         down
FastEthernet0/3            unassigned      YES     unset         down         down
FastEthernet0/4            unassigned      YES     unset         down         down
FastEthernet0/5            unassigned      YES     unset         down         down
FastEthernet0/6            unassigned      YES     unset         down         down
FastEthernet0/7            unassigned      YES     unset         down         down
FastEthernet0/8            unassigned      YES     unset         down         down
FastEthernet0/9            unassigned      YES     unset         down         down
FastEthernet0/10          unassigned      YES     unset         down         down
FastEthernet0/11          unassigned      YES     unset         down         down
FastEthernet0/12          unassigned      YES     unset         down         down
FastEthernet0/13          unassigned      YES     unset         down         down
FastEthernet0/14          unassigned      YES     unset         down         down
FastEthernet0/15          unassigned      YES     unset         down         down
FastEthernet0/16          unassigned      YES     unset         down         down
FastEthernet0/17          unassigned      YES     unset         down         down
FastEthernet0/18          unassigned      YES     unset         down         down
FastEthernet0/19          unassigned      YES     unset         down         down
FastEthernet0/20          unassigned      YES     unset         down         down
FastEthernet0/21          unassigned      YES     unset         down         down
FastEthernet0/22          unassigned      YES     unset         up             up
FastEthernet0/23          unassigned      YES     unset         down         down
FastEthernet0/24          unassigned      YES     unset         down         down

What other info can I supply to resolve this?

Thanks.

[Leo Laohoo · Accepted solution]

I think you need to configure router-on-a-stick.  

Post your DHCP configuration.

[paquinjrm]

it was indeed a question of configuring router-on-a-stick.  I'd already set up the vlans and switchports on the switch (to practice VTP) so it was just a matter of configuring the subinterfaces to match.  Quite easy, really.

Thanks for the help.

Btw, I found this tutorial that takes you step by step:

http://youtu.be/FpwllixrQQo

[mohabdel]

Hi Paquinjrm,

Router in sitck 100% wrong answer.  router in sitck for trunking ONLY.  anyway. I want you direct connect your pc to your router fa0/0  if you get IP address from your router this mean you config DHCP correct. and issue from your switch.  If you did not get any IP from your router this mean you maybe neet reconfig DHCP scope

go to your router CLI

r2600# config t

# service DHCP

#ip dhcp pool DATA

#network 192.168.10.0 255.255.255.0

#default-router 192.168.10.1

#lease infinite

# dns-server 8.8.8.8

#end

wr mem

make sure your switchport in default vlan

2600 router and 2650 switch not cisco small business devices so if you need more information please

https://supportforums.cisco.com/community/6016/lan-switching-and-routing

Thanks,

Moh

[paquinjrm]

Hi Moh,

  First, thanks for pointing out that I'm in the wrong section of the forums.  My bad.  I'll pay closer attention next time.

  Second, I tried your suggestion but it failed to work.  I cleared the configs of the router so I could start with a clean slate and followed your commands to the letter.  The host can't seem to get an IP assigned and the here's what I get with a Show IP DHCP Pool:

Router_1#show ip dhcp pool

Pool vlan1 :
 Utilization mark (high/low)    : 100 / 0
 Subnet size (first/next)       : 0 / 0
 Total addresses                : 254
 Leased addresses               : 0
 Pending event                  : none
 1 subnet is currently in the pool :
 Current index        IP address range                    Leased addresses
 192.168.10.1         192.168.10.1     - 192.168.10.254    0

  Am I missing something?

[mohabdel]

Hi Paquinijrm,

no you did not missing any.  Sorry I did miss something

# ip dhcp excluded-address 192.168.10.1 192.168.10.99

add this command with dhcp command.

-------------------

r2600# config t

# service DHCP

# ip dhcp excluded-address 192.168.10.1 192.168.10.99

#ip dhcp pool DATA

#network 192.168.10.0 255.255.255.0

#default-router 192.168.10.1

#lease infinite

# dns-server 8.8.8.8

#end

wr mem
#show IP dhcp binding

hope this time will work!