Here's my situation. It's hypothetical, but happens often enough to be a problem.
We have a generic layer 2 ethernet network switch. All of the devices connected to this switch use IP addresses in a 10.1.1.0/24 private network.
We attached a new device to this network, and it runs embedded Linux. We configured this device to use the 10.1.1.0/24 network. This device was working fine, but has mysteriously dropped off the network. We cannot connect to this device using traditional TCP/IP tools (ping,
telnet 10.1.1.100 22, etc.).
We suspect that this device somehow got reset, and reverted to its default network configuration where it wants a network like 192.168.1.0/24 or 192.168.0.0/24 (I don't remember which network). It seems to be rebooting over, and over, and over again (maybe doing a DHCPDISCOVER between reboots).
This device is still connected to the switch, and it seems to have a link connection between reboots.
Is there a way for me to probe the device from a computer which is attached to the same switch? Is there a layer 2 equivalent for the
ping command, or a broadcast ping to show me all devices connected to this lan segment?