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4800G DHCP Relay Issues 1

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cyberspace

Technical User
Aug 19, 2005
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On the 5500G setting up DHCP relay was simply a process of setting a dhcp server and then using almost the same command at the VLAN interface level. This doesn't appear to be the case with the 4800G.

I have a single stack with 2 units, currently in use for testing. I have attached one of the Windows domain controllers to this switch. The network address for vlan 1 is 10.1.1.0/24 The link back to the main current switch is as follows:

interface GigabitEthernet1/0/2
broadcast-suppression pps 500
undo jumboframe enable
poe enable
stp edged-port enable

On the other end is a 3Com 2924HPWR. I can still access the DC when on this port and recieve DHCP on the regular VLAN.

I have enabled dhcp globally on the switch.

I have defined a relay group as follows:

dhcp relay server-group 1 ip 10.1.1.1
dhcp relay server-group 1 ip 10.1.1.2

On the interface for VLAN 7 I have assigned this group:

interface Vlan-interface7
ip address 10.1.2.1 255.255.255.0
dhcp relay server-select 1

I have added and activated the scope for vlan 7 on the windows server.

When testing a machine plugged into a vlan 7 access port, DHCP does not work. A wireshark trace only shows DISCOVER packets from my laptop.

On the 5500 this was such an easy task...I have googled and I see others have mentioned the problem but not posted their solution.

Anybody know where I've gone wrong?

Many thanks

'When all else fails.......read the manual'
 
Turns out I missed a command - just in case anybody else has the same issue.

interface Vlan-interface7
ip address 10.1.2.1 255.255.255.0
dhcp select relay
dhcp relay server-select 1



'When all else fails.......read the manual'
 
I hope this works. I have had a 4200G as my core switch and DHCP like you said was a one line command. I have tried changing out the 4800G as my core multiple times and now it looks I will finally be able to do this!!!! Ahh thank you!
 
No Joy:
Here is what I have configured so far, maybe you can help me:

dhcp relay server-group 0 ip 10.12.10.4

interface Vlan-interface3
dhcp select relay
dhcp relay server-select 0

dhcp server detect

dhcp enable

My DHCP server is known working as I am currently using it on my 4200Gs. Cyberspace/anyone else have any help?
 
Sorry I was incorrect I realized I was just using an access port for my main connection and not a trunk so it could not pass all the vlan information! Cyber you have saved me a lot of pain. Thank you sir!
 
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