Dhcp not working

[luispereira75]

Hi I have 2 sites connected with fiber and one i can get DHCP working for vlans the second site i can get DHCP for the main scopes but not for the vlans, Can anyone help?

[Georg Pauwen]

Hello,

we need more information. What is the DHCP server, the IOS device ? Post the configuations of the devices at both sites...

[Mark Malone]

sounds like you might need ip helper on the vlan interfaces on 2nd site so it can reach the dhcp , just a guess though as you haven't provided any information

[luispereira75]

Site 1

Current configuration : 15796 bytes

!

version 12.2

no service pad

service timestamps debug uptime

service timestamps log datetime

service password-encryption

service sequence-numbers

!

hostname SW-201-DataCenter

!

boot-start-marker

boot-end-marker

!

!

!

no aaa new-model

clock summer-time UTC recurring last Sun Mar 1:00 last Sun Oct 2:00

switch 1 provision ws-c3750g-24ts

switch 2 provision ws-c3750g-24ts

system mtu routing 1500

ip routing

no ip domain-lookup

!

interface Vlan1

no ip address

shutdown

!

interface Vlan5

description Telefones

ip address 172.19.68.250 255.255.252.0

!

interface Vlan8

description Informatica

ip address 192.168.8.250 255.255.255.0

!

interface Vlan10

ip address 172.19.67.250 255.255.252.0

!

interface Vlan50

ip address 192.168.50.250 255.255.255.0

!

interface Vlan100

ip address 192.168.100.250 255.255.255.0

!

interface Vlan150

ip address 192.168.150.250 255.255.255.0

!

interface Vlan201

ip address 192.168.201.250 255.255.255.0

!

interface Vlan202

ip address 192.168.202.250 255.255.255.0

!

no ip classless

ip route 0.0.0.0 0.0.0.0 172.19.67.254

[luispereira75]

Hi I have Ip helper address in the config but still not forwarding the DHCP.

no aaa new-model

clock summer-time UTC recurring last Sun Mar 1:00 last Sun Oct 2:00

switch 1 provision ws-c3750g-24ts

switch 2 provision ws-c3750g-24ts-1u

system mtu routing 1500

ip routing

no ip domain-lookup

interface Vlan1

no ip address

!

interface Vlan5

description Telefones

no ip address

!

interface Vlan8

description Departamento IT

ip address 192.168.8.251 255.255.255.0

!

interface Vlan10

ip address 172.19.67.251 255.255.252.0

!

interface Vlan50

no ip address

!

interface Vlan100

ip address 192.168.100.251 255.255.255.0

!

interface Vlan150

description reparacoes eletronicas

no ip address

!

interface Vlan201

description producao

ip address 192.168.201.251 255.255.255.0

ip helper-address 172.19.64.19

!

interface Vlan202

ip address 192.168.202.251 255.255.255.0

ip helper-address 172.19.64.19

!

ip default-gateway 172.19.67.254

ip classless

ip route 0.0.0.0 0.0.0.0 192.168.100.250

ip http server

ip http authentication local

ip http secure-server

[Mark Malone]

why do you have you 2 gateways , which is it 192 address or 172 ?

[luispereira75]

No i am forwarding to a layer 3 switch that is connected to the default gateway .

[Georg Pauwen]

Hello,

which platform/device is this ?

Try configuring:

ip forward-protocol nd

in global configuration mode...

[Mark Malone]

also make sure dhcp service is on

(config)#service dhcp

[Mark Malone]

try move the helper up to switch 1 , one of the vlans see if it makes a difference , really only need a vlan interface on the layer 3 switch , otherwise its just really for reachability in mgmt.

[luispereira75]

I don´t understand what you mean i have all vlans in both layer 3 switches and the datacenter is connected to the default gateway in the site 1, the site 2 is the second layer 3 swicth with not getting the dhcp.

[Georg Pauwen]

The thing is: you are using the same address space at two different sites, as far as I can tell. Your DHCP server cannot service a remote site with the same address space as the local address space.

Am I totally off here ? Can you ping the DHCP server on site 1 from site 2, and vice versa ?

[Georg Pauwen]

Hello,

how are these sites connected ? You have configured a Vlan 10 interface at both sites, within the same address space. What is the link (layer 2 or layer 3) between the sites ?

[luispereira75]

They are connected with mono fiber and it is layer 2

[Mark Malone]

shouldn't be using this on layer 2 switch ip route 0.0.0.0 0.0.0.0 192.168.100.250 , the default is enough
you don't need SVI interfaces then if its layer 2 and trunked up to site 1 which is layer 3 switch , they can be shut down but still remain at layer 2