DHCP Relay Agent

[themightymrp]

Our core switch is a Cisco rather than a HP, I had to change its default operating mode from a Layer 2 switch to a Layer 3 switch before I started entering any config. Could this switch be the same? If its running in Layer 2 mode it wouldn't work....?

[techie08]

It will only authorise for the whole dhcp server not per scope. How do you authorise per scope?

[themightymrp]

Is DHCP-relay enabled on the switch? And does your DHCP server plug directly into this switch? I was told once that the server had to connect directly into it.

[techie08]

Is DHCP-relay enabled on the switch? And does your DHCP server plug directly into this switch? I was told once that the server had to connect directly into it.

 

yes its enabled.

[themightymrp]

Just looking at the config, should there be a setting for ip default-gateway ?

[timbo343]

It will only authorise for the whole dhcp server not per scope. How do you authorise per scope?

 

Sorry i meant activate the scope.

[timbo343]

Just looking at the config, should there be a setting for ip default-gateway ?

 

Yep, just looked though the config and he is missing.

[timbo343]

Comparing your config to mine, you need:

 

max-vlans 256

IP default-gateway {ipaddress of firewall/router (the next hop)}

 

Everything else looks ok and if you plug a device into A9 you should get a 10.74.220.x address.

Edited February 12, 2013 by timbo343

[DMcCoy]

I assume your dhcp server has 10.43.113.73 as its gateway?

[techie08]

Comparing your config to mine, you need:

 

max-vlans 256

IP default-gateway {ipaddress of firewall/router (the next hop)}

 

Everything else looks ok and if you plug a device into A9 you should get a 10.74.220.x address.

 

There is no ip default gateway set on the switch. I will do this tomorrow and see if this helps.

 

Our current default gateway for servers and clients is the default gateway of our swgfl switch. Not the ip of the HP switch.

[themightymrp]

Any further along with this?

[techie08]

Any further along with this?

 

Unfortunately not, I had to take a days leave so I will have look tomorrow.

[techie08]

Im finally on the right track (i think.) In my dhcp server i had the default gateway of the SWGFL switch (as do all my other clients and servers) so i changed this to the IP address of VLAN 1 on the HP switch and its now dishing out DHCP address for the 10.74.220 range which is great. Now however, my DHCP server (also DC) does not have an internet connection. I have also put in the IP address of the SWGFL switch on the default gateway on the HP switch but still no internet access. Edited February 14, 2013 by techie08

[timbo343]

I think you need a layer 3 switch to route the traffic also have you got

 

ip route 0.0.0.0 0.0.0.0 {firewall/router}

 

so the switch knows where to route internet traffic.

 

I am in the same boat at the moment, however i have a hp procurve 4204vl but getting a smoothie next week so will see what happens.

 

If the above line isnt right i would like to know what is the right command to route traffic to filtering or router.

[techie08]

I think you need a layer 3 switch to route the traffic also have you got

 

ip route 0.0.0.0 0.0.0.0 {firewall/router}

 

so the switch knows where to route internet traffic.

 

I am in the same boat at the moment, however i have a hp procurve 4204vl but getting a smoothie next week so will see what happens.

 

If the above line isnt right i would like to know what is the right command to route traffic to filtering or router.

 

The switch is a HP 5406zl and its a layer 3 switch. Would putting the IP address of the SWGFL switch in the default gateway on the HP switch not route internet traffic then?

 

EDIT: one thing i have noticed id that i cant ping the SWGFL switch so would this cause issues? It works because i can get the internet, just cant ping it!

Edited February 14, 2013 by techie08

[techie08]

Looks like adding the ip route done the trick.

[nev104]

Sorry to drag this back up but I am having a similar problem.

 

I have my dhcp server on the default vlan

 

I want vlan 5 to get it's ip's from dhcp on vlan 1

I have created a scope for vlan 5 in dhcp but it is not serving addresses with the below config on the core switch

 

Startup configuration:

 

; J4819A Configuration Editor; Created on release #E.10.20

 

hostname "Core Switch"

snmp-server location "xxxxxx"

max-vlans 254

module 3 type J4821B

module 4 type J4821B

module 2 type J4878B

module 1 type J4878B

interface D4

name "Internet"

speed-duplex 100-full

exit

ip default-gateway 10.74.144.1

ip routing

no timesync

snmp-server community "public" Unrestricted

vlan 1

name "DEFAULT_VLAN"

untagged A1-A4,B1-B4,C1-C4,D1-D4

ip address 10.74.144.40 255.255.240.0

ip helper-address 10.74.144.8

ip helper-address 10.74.144.9

ip igmp

exit

vlan 5

name "dhcp test"

ip address 192.168.0.1 255.255.255.0

ip helper-address 10.74.144.8

tagged A1-A4,B1-B4,C1-C4,D1-D4

exit

ip route 0.0.0.0 0.0.0.0 10.74.144.1

spanning-tree

 

Can someone help with this?