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This article focuses on "how to detect IP address conflicts in CentOS". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn how to detect IP address conflicts in CentOS.

Let's look at an example:

A linux host IP:192.168.0.25 MAC: 00:14:k2:5d:8e:b2

A windows host IP:192.168.0.25 MAC: 00:25:e4:6a:4b:f4

The IP addresses of the two hosts are the same (IP:192.168.0.25) and the MAC addresses are different

Then the windows host prompts the IP address conflict, but the linux host does not.

So how do you know if your linux host conflicts with the IP addresses of other windows hosts in the network?

Actually, it is very simple to execute on the linux host side.

# arping 192.168.0.25

Unicast reply from 192.168.0.25 [00:25:e4:6a:4b:f4] 1.390ms

If there is no information, it means my IP is unique on the network.

If you have the above information, it means that there is a host in the network whose MAC address is 00:25:e4:6a:4b:f4 and the IP address is the same as mine. At this time, you can verify it through the ifconfig command, and you will find that the local MAC address is 00:14:k2:5d:8e:b2. We can use the local area network scanning software to find the host with the MAC address 00:25:e4:6a:4b:f4, and isolate it or change the IP address.

Principle: the arping command sends the arp packets with a broadcast address, and all hosts in the Ethernet will receive the arp packets, but the local machine will not Reply any information after receiving it. When we execute the following command on the linux host:

Arping 192.168.0.25 uses eth0 by default and sends one to all hosts in the LAN:

Arp request,tell 192.168.0.25 your mac address of who has 192.168.0.25

When the windows host receives the arp packets, it replies:

I am 192.168.0.25, mac is 00:25:e4:6a:4b:f4 ", so we will receive the Reply information of the windows host whose mac address is 00:25:e4:6a:4b:f4.

At this point, I believe you have a deeper understanding of "how to detect IP address conflicts in CentOS". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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