Monitors the NDP information received by the router through the device sudo ndptool monitor sudo ndptool monitor --ifname=$4 Monitor ndp protocol on specified interface sudo ndptool monitor --ifname=$4 --msg-type=$6 Monitor ndp protocol on specified interface rs ra ns na sudo ndptool send --ifname=$4 --msg-type=$6 Send a specified type of NDP message sudo ndptool monitor --msg-type=$4 Monitor ndp protocol on specified interface rs ra ns na sudo ndptool send --msg-type=$4 Send a specified type of NDP message