You need to ping the device from the switch so you can populate the switches arp cache with the IP/Mac mapping.
From there you can then find the port
# firstly on the cisco switch you need to ping the IP address of the device ping 192.168.0.6 Sending 5, 100-byte ICMP Echos to 192.168.0.70, timeout is 2 seconds: !!!!! # you can grab the mac address connected to a cisco switch port switch01#show mac-address-table | include Gi0/6 1 d4be.d9fb.8630 DYNAMIC Gi0/6 # and get the IP Address of the connected device switch01#show ip arp | include d4be.d9fb.8630 Internet 192.168.0.6 0 d4be.d9fb.8630 ARPA Vlan1
This may only work if the host you are trying to track down is doing inter-subnet communications.
You may need to do a ping or nmap -sP subnet/subnet_mask to populate the mac-address-table on the switch.