Linux Server Admin Tools and GNU Benchmark Tools Directory, OpenSource Tools

ARP Scan tool NetScanTools

The ARP Scan Tool (AKA ARP Sweep or MAC Scanner) is a very fast ARP packet scanner that shows every active IPv4 device on your subnet. Since ARP is non-routable, this type of scanner only works on the local LAN (local subnet or network segment).

The ARP Scan Tool shows all active devices even if they have firewalls. Devices cannot hide from ARP packets like they can hide from Ping.

 

How to install arp-scan

To install arp-scan on Ubuntu or Debian:

# sudo apt-get install arp-scan

To install arp-scan on CentOS, Fedora or Redhat:

# sudo yum install arp-scan

To detect IP address with arp-scan, run the following.

# sudo arp-scan -I eth1 -l
Starting arp-scan 1.9.2 with 32 hosts (http://www.nta-monitor.com/tools-resources/security-tools/arp-scan/)
10.10.11.193 cc:4e:24:c7:71:14 test Communications Systems, Inc.
10.10.11.194 00:50:56:3e:57:25 VMware, Inc.
10.10.11.196 00:50:56:09:67:4e VMware, Inc.
10.10.11.197 00:50:56:w4:1d:fb VMware, Inc.
10.10.11.199 00:50:56:61:f8:f6 VMware, Inc.
10.10.11.202 00:50:56:a2:0d:09 VMware, Inc.
10.10.11.203 00:50:56:89:2n:a8 VMware, Inc.
10.10.11.204 00:50:56:89:27:77 VMware, Inc.
10.10.11.205 00:50:56:59:76:e7 VMware, Inc.
10.10.11.206 00:50:56:2e:3a:e3 VMware, Inc.
10.10.11.207 00:50:56:89:18:33 VMware, Inc.
10.10.11.208 00:50:56:2e:21:60 VMware, Inc.
10.10.11.209 00:50:56:1e:27:0a VMware, Inc.
10.10.11.210 00:50:56:89:24:46 VMware, Inc.
10.10.11.211 00:50:56:1e:3b:9a VMware, Inc.
10.10.11.212 00:50:56:89:3c:11 VMware, Inc.
10.10.11.216 00:50:56:2e:1e:da VMware, Inc.
10.10.11.218 00:50:56:3e:21:5c VMware, Inc.
10.10.11.220 00:0c:29:57:69:74 VMware, Inc.
10.10.11.222 00:50:56:8e:31:66 VMware, Inc.
10.10.11.213 00:50:56:89:45:00 VMware, Inc.
10.10.11.214 00:50:56:89:44:d8 VMware, Inc.
10.10.11.215 00:50:56:c4:1d:bb VMware, Inc.
10.10.11.217 00:50:56:89:3a:0f VMware, Inc.
10.10.11.219 00:50:56:49:12:db VMware, Inc.
10.10.11.221 00:50:56:89:8c:a6 VMware, Inc.

That’s it.

 

How to detect IP address conflicts

If you have any IP address conflict issue, you can see any two different MAC addresses are claiming the same IP address.