Approach - nmap scanning

1. Creating list from subnet

      i.   Single subnets

              nmap -sL -n <<subnet (10.10.10.1/24)>> | grep 'Nmap scan report for' | cut -f 5 -d ' ' 

      ii.  Multiple subnets

             nmap -sL -n <<subnet 1 subnet 2 subnet 3 (10.10.10.1/24 10.2.4.5/28 128.1.1.1/23)>> | grep 'Nmap scan report for' | cut -f 5 -d ' ' 

2. Host disovery ( available/up hosts in tbe network or list )

    nmap -sn -iL << ip / ip list >>

3. TCP scan 

      i. 20-1000 ports scan

          nmap -sV -p20-1000 -iL << ip list file >> -Pn -oA << filename >>

     ii. Full port scan 

          nmap -sV -p- -iL << ip list file >> -Pn -oA << filename >>

     iii. UDP scan

           nmap -sU --top-ports 1000 -iL << ip list>> -Pn -oA << filename >>