Link Layer Discovery Protocol (LLDP) is an independant IEEE protocol (IEEE 802.1AB) that helps with gathering/ advertising a device’s identity, capabilities, and neighbors. LLDP is Layer 2 protocol.
LLDP is usually used on network devices (switches/ routers) to find ‘neighbor’ (connected) devices, but is equally useful on servers to find details of the switch it’s connected to. This is not enabled by default on Linux, but here’s a quick guide to get it working.
$ sudo yum install lldp
$ sudo service lldpd start
$ sudo lldpcli show neighbors