Tips on how to avoid IP address conflicts

I recently had this error happened on a laptop that caused a user who used that laptop as the presentation in a meeting to present some of the ideas on the internet. The conflict also took our phone system down because that phone system had the same IP address as the laptop got from DHCP server. It’s a very rare situation where a working DHCP server assigned a taken IP address to a different devices at the same time. But it does happen sometime.

And that’s why I think Michael from 4sysops made a few useful tips on how to avoid things like this from happening. Here are the summarized points.

• Use DHCP, which is quite obvious that this is a must-have.
• Enable IP address conflict detection in DHCP server, very useful tip
• Use shorter DHCP lease times
• When working with multiple DHCP servers that are not in the same AD, assign them different block of IP addresses.
• Don’t allow end users to modify IP addresses, there is no reason for that as well. Restrict them in Group Policy.
• Work with reserved IP addresses and document it
• Backup you DHCP server several times a day, very good point.

Plus, do not allow any devices with DHCP server enabled attach to your network. Disable DHCP before connecting it to the network.