Add support for MAC address when doing a diagnostic packet capture

[kquinsland]

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Is your feature request related to a problem? Please describe.

From time to time, I need to capture packets from devices before they have an IP address / before I know what the IP address is of the device.

E.G.: I have a device with an unknown configuration (will it request DHCP on start up? does it have a static IP configured?) that I will plug into my network. I want to start packet capture on the device before it is powered up so that I can be sure I capture ALL traffic. The only way to do this is by telling tcpdump to capture traffic with an ether host filter.

Describe the solution you like

I would like the packet capture field to also accept a mac address.
Currently, if you try to insert a MAC address, you'll get an error about the input value not being a valid IP address.

Describe alternatives you considered

Currently, I need to do something like this via SSH:

$ tcpdump -i untrustedVlan -w device_under_test.pcap ether host de:ad:be:ef:ab

It would be nice if I could use the web interface to capture the packets the same way I can if I had known the IP address of the device.

Additional context

Add any other context or screenshots about the feature request here or links to relevant forum thread or similar

[AdSchellevis]

720ffdc should do the trick. We'll try to ship this in 23.1