DHCP Relay through Flex Network 5510 Switch

[Tiwari]

Dear all

I have HPE Flex Network 5510 as Layer 3 and office connect 1920s Devices with sophos XG Firewall.

Firewall ip- 172.16.1.1, Layer 3 IP-172.16.1.2 with four vlan.

Vlan 10 IP address-172.16.10.1

Vlan 20 Ip adress- 172.16.20.1

Layer3 Directly connected with lan port of Sophos.

Vlan Configuration

ip address 172.16.10.1 255.255.252.0
dhcp select relay
dhcp relay server-address 172.16.1.1

i can ping vlan ip with my layer 2 Switch(office connect 1920s) but not getting ip through firewall 

is that above configuration is correct??

[Ivan_B · Accepted solution]

Hi @Tiwari !

Vlan-interface10 configuration seems to be correct, just be sure you did not forget this global command:

system-view
 dhcp enable

Also, your Sophos firewall should have DHCP pools for 172.16.10.0/22 and 172.16.20.0/22 ranges.

You can run a packet capture on Sophos to see if 5510 relays DHCP messages from your end-clients in Vlans 10 and 20, I am sure it has such feature. There you will also see if Sophos replies to such requests. Maybe checking logs of DHCP process in Sophos also makes sense.