Why does nmap ping scan over a VPN link return all hosts alive?
- by ewwhite
I'm curious as to why running an nmap -sP (ping scan) on a remote subnet linked via a Cisco site-to-site IPSec tunnel returns "host up" status for every IP in the range.
[root@xt ~]# nmap -sP 192.168.108.*
Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2012-11-22 14:08 CST
Host 192.168.108.0 appears to be up.
Host 192.168.108.1 appears to…