I learned recently that DHCP lets you assign specific IP’s to certain MAC addresses.
Previously I had always used static IP’s for devices, but sometimes the UI for certain devices is kind of cumbersome. Using IR remotes or arrow keys on the side of some devices is no fun when you have a lot of them to do. The static IP’s also would need to be configured again if you needed to reset the device for whatever reason.
Set up
To set up DHCP just log into whatever device hosts your DHCP server, usually a router or a switch, and ask it to assign an IP to whatever the MAC address of your device is.
On most of my devices this change propagated to the devices almost instantly. On some others I had to ask them to renew their DHCP manually. And if the device was less important, I just waited for the DHCP lease time to run out for it to get the new address.
Notes
Obviously, this is only useful if you use the exact same hardware regularly. If you have to swap a device you will have to update the DHCP server again.
It also assumes you have a DHCP server. On some live events you end up with a cheap switch with no DHCP server on it. I suppose you could technically run a DHCP server on random machine, but I can’t think of a situation where that would be faster than just programming static IP’s.
Another disadvantage involves redundancy. For whatever reason my router does not have the ability to export the pre-assigned IP’s. So if the router randomly explodes, I don’t have an easy way to make the system redundant. Basically if I plug in a fresh router that isn’t configured yet, all the devices set to get addresses from DHCP will get NEW addresses, unless you hade preconfigured the second router with the DHCP assignments.
EDIT: I forgot my router has the ability to export all settings, but it doesn’t help much if your backup router is a different model. Still would be really nice to be able to export a table of the DHCP settings alone.
If you’re curious about how to make the system more robust, I’d ask the internet for advice on how to make redundant DHCP servers. It’s probably not going to be cheap though.