What is IP conflict issue?

What is IP conflict issue?

Whenever we are going to configure a IP address on a device, is the same IP address is configured on another device already before this, our device will generate a error message of IP conflict.

How this is happening?

Whenever we are configuring the IP address on a system, the system will generate a gratuitous arp for the same ip address to check duplicacy. The gratuitous arp will be like a arp request. So whenever the device who already configured with the same IP receive this message will respond with a ARP reply. The system where you are configuring the IP after getting the arp response for the IP address will generate a IP Conflict error and will not configure the IP address to it.