DHCP Exchange - Options 55 & 60


#1

We have a partner who wants the full DHCP exchange of our devices. They say they need Options 55 and 60. Using wireshark on some Imp003 we have I can only ever see Option 55 being sent.

Is it normal for Option 60 not to be sent? Any other way we might be able to snoop on this and find out what is being sent in the DHCP exchange?

Thanks


#2

55 is normal - this is how the device says it’d like the subnet mask, default gateway, DNS server, etc.

60 is not normal, unless the device is expecting some special vendor parameter to be served by the DHCP server. See https://www.paloaltonetworks.com/documentation/80/pan-os/pan-os/networking/dhcp/dhcp-options/dhcp-options-43-55-and-60-and-other-customized-options - we do not expect or need any vendor parameters from the DHCP server and so don’t send option 60.

There’s no option to send additional options to the DHCP server.


#3

Option 60 is – unless things have changed – usually only used for network-booting clients that use PXE.

At least, that’s how I remember it – I’ve written at least two PXE-boot servers, but it was a long time ago.

Since the imp doesn’t PXE-boot, option 60 is irrelevant.