Foreword
Survival host scanning large in cyberspace
achieve
nmap -v -sn -PE -n --min-hostgroup 1024 --min-parallelism 1024 -oX nmap_output.xml www.lijiejie.com/16-sn not scan port, only ping host
-PE ICMP echo is determined by the host is alive
-n Do not reverse resolve IP addresses to domain names
--min-hostgroup 1024 1024 minimum packet to IP addresses when IP too, need to be grouped nmap, then serial scan
--min-parallelism 1024 This parameter is very critical, in order to make full use of system and network resources, we will define a minimum number of probes 1024
-oX nmap_output.xml the results in XML output format, the file name nmap_output.xml
When the amount is less need for host survival determination, may be eliminated --min-hostgroup --min-parallelism and scan parameters. After finishing nmap_output.xml expressions with positive survival can be obtained and the corresponding host ip.