nmap reports host up when it isn't
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martianway
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Published on 2010-12-29T07:52:35Z
Indexed on
2010/12/29
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Hit count: 242
On an Ubuntu VM I ran:
sudo nmap -sP 192.168.0.*
This returned:
Starting Nmap 5.00 ( http://nmap.org ) at 2010-12-28 22:46 PST
Host 192.168.0.0 is up (0.00064s latency).
Host 192.168.0.1 is up (0.00078s latency).
Host 192.168.0.2 is up (0.00011s latency).
.
.
.
Host 192.168.0.254 is up (0.00068s latency).
Host 192.168.0.255 is up (0.00066s latency).
The problem is I only have 4 live machines on 192.168.0.* so why did nmap report every ip in the subnet has a live host?
The ip address of the Ubuntu machine is 192.168.28.131 From this VM I can ping the live systems on my internal subnet 192.168.0.* and get the expected response. And if I ping a machine that doesn't exist I can get no response as expected.
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