Question

Problem with Vlan DHCP, wrong Subnet IP address

VLAN, DHCP, L3 Switches, Subnets

Hi, I have a problem with my Vlan, the problem is; I have got a Win2k Server with DHCP configured, 1x Superscope, with 3 scopes underneath it, subnets 192.168.2.0 (range 100-254), 192.168.20.0 (range 100-254), and 192.168.30.0 (range 100-254). When I manually enter the to the port according Ip address on my client PC, it all works a treat, but when I request a DHCP address, it just gives me a 192.168.2.0 IP, and I cannot access any resources. Here is my config;
!Current Configuration:

!System Description "Dell 24 Port Gigabit Ethernet, 2.0.0.12, VxWorks5.5.1"

!System Software Version 2.0.0.12

!

configure

vlan database

vlan 10,20,30

vlan association subnet 192.168.2.0 255.255.255.0 10

vlan association subnet 192.168.20.0 255.255.255.0 20

vlan association subnet 192.168.30.0 255.255.255.0 30

exit

stack

member 1 1

exit

switch 1 priority 1

ip address 192.168.1.1 255.255.255.0

ip default-gateway 192.168.2.201

ip routing

ip route 0.0.0.0 0.0.0.0 192.168.2.201

bootpdhcprelay enable

bootpdhcprelay maxhopcount 16

bootpdhcprelay serverip 192.168.2.10

bootpdhcprelay cidridoptmode

ip helper-address 192.168.2.1 192.168.2.10 37

ip helper-address 192.168.2.1 192.168.2.10 49

ip helper-address 192.168.2.1 192.168.2.10 137

ip helper-address 192.168.2.1 192.168.2.10 138

ip helper-address 192.168.20.1 192.168.2.10 37

ip helper-address 192.168.20.1 192.168.2.10 49

ip helper-address 192.168.20.1 192.168.2.10 137

ip helper-address 192.168.20.1 192.168.2.10 138

ip helper-address 192.168.30.1 192.168.2.10 37

ip helper-address 192.168.30.1 192.168.2.10 49

ip helper-address 192.168.30.1 192.168.2.10 137

ip helper-address 192.168.30.1 192.168.2.10 138

interface vlan 10

name "Servers"

routing

ip address 192.168.2.1 255.255.255.0

ip netdirbcast

exit

interface vlan 20

name "Sales"

routing

ip address 192.168.20.1 255.255.255.0

ip netdirbcast

exit

interface vlan 30

name "Accounts"

routing

ip address 192.168.30.1 255.255.255.0

ip netdirbcast

exit

username "michi" password 4f70cfb1451a1b0ce0b872421bee6c1c level 15 encrypted

!

interface ethernet 1/g1

switchport mode general

switchport general pvid 10

no switchport general acceptable-frame-type tagged-only

switchport general allowed vlan add 10,20,30

exit

!

interface ethernet 1/g3

switchport mode general

switchport general pvid 10

no switchport general acceptable-frame-type tagged-only

switchport general allowed vlan add 10,20,30

exit

!

interface ethernet 1/g4

switchport mode general

switchport general pvid 20

no switchport general acceptable-frame-type tagged-only

switchport general allowed vlan add 20

exit

!

interface ethernet 1/g5

switchport mode general

switchport general pvid 10

no switchport general acceptable-frame-type tagged-only

switchport general allowed vlan add 10,20,30

exit

!

interface ethernet 1/g8

switchport mode general

switchport general pvid 30

no switchport general acceptable-frame-type tagged-only

switchport general allowed vlan add 30

exit

!

interface ethernet 1/g24

switchport mode general

switchport general pvid 10

no switchport general acceptable-frame-type tagged-only

switchport general allowed vlan add 10,20,30

exit

exit

Any help or comments are welcome.
Thank you
Micahel

Unfortunately for us, this is working as designed, designed like #&!%.

Superscopes override individual scopes. You will need to create individual scopes for each VLAN subnet. I had the same problem. I wanted to use superscopes to try and make management easier but it creates the problem that you described. Once I created individual scopes for each VLAN subnet, my problems went away.

Take a look at the following MS KB articles
169290 - DHCP reservations do not get assigned from a superscope - notice the line: This is happening because a DHCP server normally hands out addresses from a superscope starting with the first scope. After that scope is full, the server starts handing out addresses from the second scope, third scope, and so on.

186341 - Superscoping vs supernetting

I had been advise that I also need to add option 82 (DHCP-Relay support) to my DHCP server in predifined options: http://slaptijack.com/networking/what-is-dhcp-option-82/

To enable DHCP-relay support:
Using DHCP Server Management console (dhcpmgmt.msc) -> -> Right Click -> Set Predefined Options..., you can add option 82 as a customized option for DHCP Server

Does anyone know what to select?

Thanks


Hello thanks for all your inputs;
I have just gone to my DHCP server which is connected to port 1/g1 Vlan10 and disabled the scope for 192.168.2.0 subnet, as this is mainly used for servers with fixed IP addresses and isn't really necessary, now when I plug my client PC into port 1/g4 I receive a 192.168.20.0 address and when I plug it into port 1/g8 I receive a 192.168.30.0 address. Its working a treat. :)
One last thing, I cannot access the internet once I received a 192.168.20.0 or 192.168.30.0 IP address can you please tell me where I have gone wrong, must be something to do with my routes.

Thank you