Sorry for the delay, I have - Page 2

Andrew White · ‎07-09-2014

Hello,

I'm trying to build a typology similar to my work in GNS3, I'm using routers with the NM-16ESW module for 16 switch ports. Anyway I'm trying to get the host on the VLAN 90 switch an IP address via DHCP but it's having none of it. Core 1 and 2 are using HSRP for all our VLANs, I though the best way to add a DHCP server using a router would be to add it to both cores and using /30 subnets and advertise into OSPF and add the ip-helper address to the VLANs on each core. Someone did suggest making the 2 ports for the DHCP server a port channel, but I wasn't sure how I woudl configure this on the to cores.

Host 1

no ip routing

!
interface FastEthernet0/0
ip address dhcp
no ip route-cache
duplex auto
speed auto

90-Switch (layer 2)

no ip routing

!
interface FastEthernet1/0

Description Host 1
switchport access vlan 90
duplex full
speed 100

!

interface FastEthernet1/14

switchport trunk native vlan 23
switchport trunk allowed vlan 1,23,90,1002-1005
switchport mode trunk
duplex full
speed 100
!
interface FastEthernet1/15
switchport trunk native vlan 23
switchport trunk allowed vlan 1,23,90,1002-1005
switchport mode trunk
duplex full
speed 100

!
interface Vlan1
no ip address
no ip route-cache
shutdown
!
interface Vlan23
ip address 192.168.23.90 255.255.255.0

Core1

interface Port-channel1
switchport mode trunk

!

interface FastEthernet1/0
switchport mode trunk
duplex full
speed 100
channel-group 1 mode on
!
interface FastEthernet1/1
switchport mode trunk
duplex full
speed 100
channel-group 1 mode on

interface FastEthernet1/4
description DHCP Server
no switchport
ip address 192.168.41.2 255.255.255.252
duplex full
speed 100

interface FastEthernet1/13
switchport trunk native vlan 23
switchport trunk allowed vlan 1,2,23,100,1002-1005
switchport mode trunk
duplex full
speed 100
!
interface FastEthernet1/15
switchport trunk native vlan 23
switchport trunk allowed vlan 1,2,23,90,1002-1005
switchport mode trunk
duplex full
speed 100

!
interface Vlan1
no ip address
shutdown
!
interface Vlan2
ip address 128.101.10.69 255.255.0.0
standby 2 ip 128.101.10.70
standby 2 preempt
!
interface Vlan20
ip address 192.168.20.253 255.255.255.0
standby 20 ip 192.168.20.254
standby 20 preempt
!
interface Vlan21
ip address 192.168.21.253 255.255.255.0
ip helper-address 192.168.21.1
standby 21 ip 192.168.21.254
standby 21 preempt
!
interface Vlan23
ip address 192.168.23.253 255.255.255.0
standby 23 ip 192.168.23.254
standby 23 preempt
!
interface Vlan30
ip address 192.168.30.253 255.255.255.0
standby 30 ip 192.168.30.254
standby 30 preempt
!
interface Vlan40
ip address 192.168.40.253 255.255.255.0
standby 40 ip 192.168.40.254
standby 40 preempt
!
interface Vlan50
ip address 192.168.50.253 255.255.255.0
standby 50 ip 192.168.50.254
standby 50 preempt
!
interface Vlan60
ip address 192.168.60.253 255.255.255.0
standby 60 ip 192.168.60.254
standby 60 preempt
!
interface Vlan70
ip address 192.168.70.253 255.255.255.0
standby 70 ip 192.168.70.254
standby 70 preempt
!
interface Vlan80
ip address 192.168.80.253 255.255.255.0
standby 80 ip 192.168.80.254
standby 80 preempt
!
interface Vlan90
ip address 192.168.90.253 255.255.255.0
ip helper-address 192.168.41.1
standby 90 ip 192.168.90.254
standby 90 preempt
!
interface Vlan100
ip address 192.168.100.253 255.255.255.0
ip helper-address 192.168.41.1
standby 100 ip 192.168.100.254
standby 100 preempt
!
router ospf 1
router-id 1.1.1.1
log-adjacency-changes
network 192.168.41.0 0.0.0.3 area 0
network 192.168.90.0 0.0.0.255 area 0
network 192.168.100.0 0.0.0.255 area 0

Core 2

interface Port-channel1
switchport mode trunk

!

interface FastEthernet1/0
switchport mode trunk
duplex full
speed 100
channel-group 1 mode on
!
interface FastEthernet1/1
switchport mode trunk
duplex full
speed 100
channel-group 1 mode on

!

interface FastEthernet1/4
description DHCP Server
no switchport
ip address 192.168.41.6 255.255.255.252
duplex full
speed 100

!

interface FastEthernet1/14
switchport trunk native vlan 23

switchport trunk allowed vlan 1,2,23,90,1002-1005
switchport mode trunk
duplex full
speed 100
!
interface FastEthernet1/15
switchport trunk native vlan 23

switchport trunk allowed vlan 1,2,23,100,1002-1005
switchport mode trunk
duplex full
speed 100

interface Vlan2
ip address 128.101.10.68 255.255.0.0
standby 2 ip 128.101.10.70
standby 2 priority 109
standby 2 preempt
!
interface Vlan20
ip address 192.168.20.252 255.255.255.0
standby 20 ip 192.168.20.254
standby 20 priority 109
standby 20 preempt
!
interface Vlan21
ip address 192.168.21.252 255.255.255.0
standby 21 ip 192.168.21.254
standby 21 priority 109
standby 21 preempt
!
interface Vlan23
ip address 192.168.23.252 255.255.255.0
standby 23 ip 192.168.23.254
standby 23 priority 109
standby 23 preempt
!
interface Vlan30
ip address 192.168.30.252 255.255.255.0
standby 30 ip 192.168.30.254
standby 30 priority 109
standby 30 preempt
!
interface Vlan40
ip address 192.168.40.252 255.255.255.0
standby 40 ip 192.168.40.254
standby 40 priority 109
standby 40 preempt
!
interface Vlan50
ip address 192.168.50.252 255.255.255.0
standby 50 ip 192.168.50.254
standby 50 priority 109
standby 50 preempt
!
interface Vlan60
ip address 192.168.60.252 255.255.255.0
standby 60 ip 192.168.60.254
standby 60 priority 109
standby 60 preempt
!
interface Vlan70
ip address 192.168.70.252 255.255.255.0
standby 70 ip 192.168.70.254
standby 70 priority 109
standby 70 preempt
!
interface Vlan80
ip address 192.168.80.252 255.255.255.0
standby 80 ip 192.168.80.254
standby 80 priority 109
standby 80 preempt
!
interface Vlan90
ip address 192.168.90.252 255.255.255.0
ip helper-address 192.168.41.5
standby 90 ip 192.168.90.254
standby 90 priority 109
standby 90 preempt
!
interface Vlan100
ip address 192.168.100.252 255.255.255.0
ip helper-address 192.168.41.5
standby 100 ip 192.168.100.254
standby 100 priority 109
standby 100 preempt
!
router ospf 1
router-id 2.2.2.2
log-adjacency-changes
network 192.168.41.4 0.0.0.3 area 0
network 192.168.90.0 0.0.0.255 area 0
network 192.168.100.0 0.0.0.255 area 0

On the host 1 if I run a "shut" , "no shut" on fa 0/0 and run DHCP debug commands on the DHCP server I get this:

*Mar 1 00:36:19.915: DHCPD: Sending notification of DISCOVER:

*Mar 1 00:36:19.915: DHCPD: htype 1 chaddr cc0a.3714.0000
*Mar 1 00:36:19.919: DHCPD: remote id 020a0000c0a8290100000000
*Mar 1 00:36:19.919: DHCPD: circuit id 00000000
*Mar 1 00:36:19.919: DHCPD: DHCPDISCOVER received from client 0063.6973.636f.2d63.6330.612e.3337.3134.2e30.3030.302d.4661.302f.30 on interface FastEthernet0/0.
*Mar 1 00:36:19.919: DHCPD: Seeing if there is an internally specified pool class:
*Mar 1 00:36:19.919: DHCPD: htype 1 chaddr cc0a.3714.0000
*Mar 1 00:36:19.919: DHCPD: remote id 020a0000c0a8290100000000
*Mar 1 00:36:19.919: DHCPD: circuit id 00000000
*Mar 1 00:36:19.919: DHCPD: there is no address pool for 192.168.41.1.
*Mar 1 00:36:19.935: DHCPD: Sending notification of DISCOVER:
*Mar 1 00:36:19.935: DHCPD: htype 1 chaddr cc0a.3714.0000
*Mar 1 00:36:19.935: DHCPD: remote id 020a0000c0a8290501000000
*Mar 1 00:36:19.935: DHCPD: circuit id 00000000
*Mar 1 00:36:19.935: DHCPD: DHCPDISCOVER received from client 0063.6973.636f.2d63.6330.612e.3337.3134.2e30.3030.302d.4661.302f.30 on interface FastEthernet0/1.
*Mar 1 00:36:19.935: DHCPD: Seeing if there is an internally specified pool class:
*Mar 1 00:36:19.935: DHCPD: htype 1 chaddr cc0a.3714.0000
*Mar 1 00:36:19.935: DHCPD: remote id 020a0000c0a8290501000000
*Mar 1 00:36:19.935: DHCPD: circuit id 00000000
*Mar 1 00:36:19.935: DHCPD: there is no address pool for 192.168.41.5.

Thanks

Andrew White · ‎07-18-2014

Let me try this first, did it work for you if you keep OSPF and have the host setup like above?

I want to eventually add DHCP to the 100 switch to via this DHCP server and not use routers as hosts and use my virtualbox win 7 image as a host.

I'm using the 3725 switches everywhere I think, but turn off routing for the L2 switches.

petenixon · ‎07-18-2014

I redid the lab with both switches and attached the configs (relevant output). I wasn't able to test Paul's method (only just saw the post!), but this basic config works with ip routing disabled on both routers.

Andrew White · ‎08-05-2014

Sorry for the delay, I have been away. So you are not using 1 of the interface on the DHCP server and have removed L3?

DHCP lab issue