Find out MAC addresses in LAN (without IP address)?

Question

Network administration

whether it is possible to learn MAC-addresses of the connected devices to an old unmanaged switch?
unknown IP range and subnet, DHCP IP address is not issued.

Answer 1

arp -a

Answer 2

arp-scan in Linux, or IP Scan in Mikrotik

Answer 3

Many useful things have been added to IPv6, in particular, there is no broadcast, and therefore no ARP, but multicast instead.
The multicast group ff02::1 includes all devices on the local network, if you ping it with ping6 -I eth0 ff02::1 (instead of eth0 you need to substitute the name of your network interface that "looks" into the local network), then all included in this device moment.
The MAC can be calculated from the link-local address from which the device responded, or look in the NDP table ip -6 neighbor show (the NDP table is analogous to the ARP table for IPv6).
The trick is that IPv6 just works - if the machine is turned on, its interfaces have at least link-local addresses and they can be fully used.
For Windows, the commands will be ping6 -s ff02::1%4 (instead of 4, you need to substitute the name of your network interface that "looks" to the local network)
Show the contents of the NDP table netsh int ipv6 show neigh
I do not use Windows - I googled the commands - I can be wrong. ..