Finding the right gateway IP address on a /24 network
I'm currently learning how to analyze network packets using wireshark, I was given a pcap file to identify the right gateway address and add a route to my machine and access the internal network.
I take a look on the ARP request "who has x.x.x.x? Tell xx.xx.xx.xx"
However when I add the routing on the table, I got an error: RTNETLINK answers: No such process (Which I think I didn't get the right gateway for the x.x.x.x)
May I know the other ways of identifying the right gateway besides from filtering ARP requests?