1

How does one list the options that are sent to a client from a DHCP server? Using a utility run from bash?

Improve this question
2
  • Noting that the bash command-line is just a command-line, and doesn't affect the ability to list DHCP options. Commented Sep 2, 2021 at 19:05
  • You can monitor the DHCP traffic by installing and using wireshark. The actual DHCP "options" aren't saved anywhere - they're applied to the system, and reflected in the running system's configuration, until something changes them. Commented Sep 2, 2021 at 21:01

3 Answers 3

Reset to default
2

You can use tshark, the commandline version of wireshark, tshark -tad -nn -VOdhcp -ixenbr0 -f 'ip and udp port 67'

Improve this answer
2

The only way to see the options (unless the machine you are running this on is the client, then you can see the effect of the options) is to capture the traffic for the DHCP exchange.

So you use anything you like to monitor network traffic (wireshark, tshark, tcpdump, ...). There's also a dedicated tool called dhcpdump.

Note that you might not see what's going on with another client if your network setup doesn't allow to capture the traffic between the DHCP server and that client.

Improve this answer
2

Assuming you have access to at least one dhcp client machine, the received DHCP options can be found in /var/lib/dhcp/dhclient.leases.

This question should probably be marked as a duplicate of How to know DHCP options value on debian/ubuntu and other linux

Improve this answer

You must log in to answer this question.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.