I need for the machines in my LAN to have static (by which I mean constant) private IP addresses. Is it possible to configure the Time Capsule to assign IP address based on MAC address, so the hosts can simply use DHCP and get the same address each time?

(Note: I'm only concerned with the private IP addresses - 192.168.1.*. Not with my TC's WAN address.)

1 Answer 1


The feature you are looking for is called "DHCP". This does exactly what you want, assign an IP address constantly given a specific MAC Address.

Open up Airport Utility.app, click your Time Capsule, then "Manual Setup". When the management dialog loads, click "Internet" up at the top, then "DHCP" in the category/tab bar.

Airport DHCP Screen

From there, you can click the plus in the bottom-left hand side of "DHCP Reservations". This will open up a dialog that allows you to create a reservation via MAC Address, or "DHCP Client ID".

Airport - Add DHCP Reservation

Fill in a system name (does not necessarily have to be the specific hostname), click MAC Address, then Continue.

Airport - Add DHCP Reservation Step 2

Fill in the MAC address, choose an IP address, then click Done, and then Update the Time Capsule!

When the client computer next refreshes it's IP address (most computer's do this once every two hours or so), it should pick up the new reservation, now and forever.

Alternatively you can just shut the interface on the computer and turn it back one. Or go into Advanced and manually renew the lease. etc. etc.

  • Excellent! I had no idea that DHCP reservations existed. One mildly puzzling thing: I have my Airport DHCP range set to .2 - .100, but was able to set up MAC-based reservations of .101, .102, and .103. Is that okay? dangerous? it works; I know that much.
    – Chap
    Commented Aug 31, 2011 at 22:12
  • IMO, it's better that reservations take place outside of the actual dynamic range, so static clients don't eat up "dynamically assigned" IPs. The router will give out whatever you tell it to, so it's just fine to have higher numbered addresses like that. Commented Aug 31, 2011 at 23:48

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .