Switches, Hubs, and Modems
cancel
Showing results for 
Search instead for 
Did you mean: 

DHCP-relay

SOLVED
Go to solution
abril
Occasional Contributor

DHCP-relay

Hi all!

I have a switch as DHCP relay agent. The switch has two VLANs, the DHCP server is set with two scopes. My problem is that the second VLAN is not receiving an ip address of its scope. Does anyone know what I am missing?

Thanks!

the configuration is listed below:

hostname "ProCurve Switch 3500yl-24G"
module 1 type J86xxA
ip routing
snmp-server community "public" Unrestricted
vlan 1
name "DEFAULT_VLAN"
untagged 1-12
ip address a.b.c.d 255.255.255.0
no untagged 13-24
exit
vlan 2
name "VLAN2"
untagged 13-24
ip helper-address a.b.c.e
ip address w.x.y.z 255.255.255.0
exit
7 REPLIES
Jeff Carrell
Honored Contributor
Solution

Re: DHCP-relay

config looks good...nothing missing that i see...sounds more like srvr side issue...

questions:

1) what port is the dhcp srvr connected to?

2) can you statically assign an ip addr to a computer in vlan 2 and then ping the dhcp srvr?

3) what is the dhcp srvr's def g/w addr?


hth...jeff
abril
Occasional Contributor

Re: DHCP-relay

Well... actually the DHCP server is assigning IP addresses to the first VLAN, and it is on the port 1.
Pieter 't Hart
Honored Contributor

Re: DHCP-relay

The switch config seems right.
a dhcp request comming from vlan2 is forwarded to a.b.c.e as comming from w.x.y.z.
The dhcp-server should send a dhcp-offer from the scope w.x.y.a send it back to w.x.y.z wich must forward it within vlan2.

You configured the dhcp-server with two scopes. Did you use a superscope? (you should not have).
Do you have multiple DHCP-servers?

abril
Occasional Contributor

Re: DHCP-relay

I have one DHCP server on linux, I already configured the two scopes and I'm not using a superscope.

The second VLAN never receives the offer, in fact, the DHCP server is unreachable to the VLAN 2.

I don't know what is happening.

Regards,
Jeff Carrell
Honored Contributor

Re: DHCP-relay

sounds like missing def g/w on dhcp server...

the dhcp server should be able to ping the vlan ip addr of the switch...

hth...jeff
cenk sasmaztin
Honored Contributor

Re: DHCP-relay

dhcp server default gateway address must be vlan 1 ip address
cenk

RicN
Valued Contributor

Re: DHCP-relay


April, did your problem got solved?

What software did you use on your 3500?

There was some bugs that corrupted dhcp relay packets in releases like 13.27 and similar. This was fixed in the newer 13.4* operating system images.

Check the release notes:

http://cdn.procurve.com/training/Manuals/yl-zl-RelNotes-K1349-59914720.pdf