macosterminaldnsip-addressreverse-dns

macOS terminal run Reverse DNS on LAN devices to get hostnames

I made some research and can't find a solution, I'm starting to think this is not possible.

I'm running arp -a in my terminal and I'd like to get the hostnames of the LAN devices.

host x.x.x.x returns:

Host x.x.x.x.in-addr.arpa. not found: 3(NXDOMAIN)

nslookup x.x.x.x returns:

** server can't find x.x.x.x.in-addr.arpa: NXDOMAIN

Is there a way to do this?

Solution

  • I found a way thanks to @gordon-davisson who set me on the right path.

    First I get the gateway IP with: route get default | grep gateway

    Then for every LAN device I run: host LAN_IP Gateway_IP

    This returns:

    Using domain server:
Name: 192.168.x.x
Address: 192.168.x.x#x
Aliases: 

x.x.168.192.in-addr.arpa domain name pointer LAN-host-name.

    I parse the response to get the name displayed at the end.

    Side note: it still doesn't display the LAN host-names with arp -a after that.