PowerConnect 6248P - Missing option 82 sub option 2 from relay

Question

Hi,I'm in the process of configuring a DHCP relay on some old 6248p (firmware 3.3.18.1) and I've got the leases working but I'm trying to make use of Option 82 and that's where it's not working entirely. I seem to have both sub options for the client vlan configured on the stack: access-lvl#show dhcp l2relay all DHCP L2 Relay is Enabled. Interface L2RelayMode TrustMode ---------- ----------- -------------- ch3 Enabled trusted VLAN Id L2 Relay CircuitId RemoteId --------- ---------- ----------- ------------ 30 Enabled Enabled Access-Lvl My DHCP server is dehind the LAG ch3 above, my endpoints on vlan 30 access ports.Here is some extract of the running config I use for testing: !Current Configuration: !System Description 'PowerConnect 6248P, 3.3.18.1, VxWorks 6.5' !System Software Version 3.3.18.1 !Cut-through mode is configured as disabled ! configure vlan database vlan 30,220 vlan routing 220 1 vlan routing 30 2 vlan association subnet 192.168.30.0 255.255.255.0 30 vlan association subnet 192.168.220.0 255.255.255.0 220 exit arp dynamicrenew arp timeout 900 arp resptime 3 arp retries 3 bootpdhcprelay cidridoptmode interface vlan 30 routing ip address 192.168.30.253 255.255.255.0 ip helper-address 192.168.220.1 dhcp exit interface vlan 220 routing ip address 192.168.220.254 255.255.255.0 exit ip dhcp snooping ip dhcp snooping vlan 30,220 ip dhcp snooping database write-delay 900 no ip dhcp snooping verify mac-address dhcp l2relay dhcp l2relay vlan 30 dhcp l2relay circuit-id vlan 30 dhcp l2relay remote-id Access-Lvl vlan 30 ! interface ethernet 2/g23 mtu 9216 switchport access vlan 30 exit ! interface port-channel 3 ip dhcp snooping trust ip dhcp snooping log-invalid hashing-mode 6 spanning-tree cost 10000 spanning-tree mst 0 external-cost 10000 switchport access vlan 220 exit However, when inspecting the client DHCP discover relayed to the server, I do not see sub option 2 on the frame, only sub option 1 is present: So Circuit ID is there as expected and configured, but Remote ID is missing...Any idea what I'm missing here? Thanks!

DELL-Josh Cr · Answer

Hi Cagrain, It looks like you have done a lot of the troubleshooting already. If you remote Access-lvl from the command does it work? dhcp l2relay remote-id vlan 30.

Casgrain · Answer

Hi,

I've done more testing and only the command "bootpdhcprelay cidridoptmode" will insert Option 82. Negate it and no option 82 inserted in frame.

Any other "dhcp l2relay" command have no impact whatsoever on the insertion of Option 82 ("dhcp l2relay trust" on an interface which will indeed enforce the option 82 on ingress traffic, but it's not meant to insert it in anyway).

Simple as that, no subtion of "bootpdhcprelay" to insert sub options and "l2relay" doesn't insert anything, so I think this is broken. Confirmation from a Dell tech would be great.

Casgrain · Answer

@DELL-Josh Cr

That's not a valid command, requires the string:

access-lvl(config)#no dhcp l2relay remote-id vlan 30

access-lvl(config)#dhcp l2relay remote-id vlan 30
                                               ^
% Invalid input detected at '^' marker.

DELL-Josh Cr · Answer

Try the steps in this thread https://dell.to/2E0deuP

Casgrain · Answer

@DELL-Josh Cr  No luck, that didn't help.

DELL-Josh Cr · Answer

I haven't been able to find anything else for why it doesn't work.

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PowerConnect 6248P - Missing option 82 sub option 2 from relay

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