#!/bin/bash

FILE='/var/lib/dhcp/dhcpd.leases'

cat $FILE | sed '/#/d' | grep "lease\|client-hostname\|hardware ethernet\|binding state" | sed 's/[;|"]//g' | awk '{
    #print $0;

    if($1=="lease"){
        #print $1;
        if(s!="") print s;
        s=$2;
    }
    else if($1=="hardware") s=s"\t"$3;
    else if($1=="client-hostname") s=s"\t"$2;
    else if($1=="binding") s=s"\t"$3;
} END{ print s;}' | sort | uniq | grep active