IP, routing and IPv6

Mac has a self-assigned IP address

If the Mac gets no answer from a DHCP server, it gives itself a link-local address from 169.254.0.0/16. This address does not reach the internet.

Applies to: macOS 13 Ventura and later for the System Settings steps. The Terminal commands work on all current macOS versions.Checked: 29 October 2026

Symptoms

Network settings say that the service has a self-assigned IP address.
The IP address starts with 169.254.
The Mac is connected to Wi-Fi or Ethernet, but it has no internet.

Likely causes

No DHCP answer. The router or DHCP server did not answer. The ipconfig man page says macOS then can assign a link-local address.
A full DHCP pool. The router has no free addresses to give.
A cable, adapter or Wi-Fi link fault. The DHCP request does not reach the router.
A firewall or filter. Security software can block the DHCP request or the answer.

How to check

Find the device name of each network port, for example en0 for Wi-Fi.
```
networksetup -listallhardwareports
```
Show the IPv4 address of the interface.
```
ipconfig getifaddr en0
```
Show the DHCP packet that the Mac accepted. No output means that DHCP did not work.
```
ipconfig getpacket en0
```
Show the service's settings. Configure IPv4 must be Using DHCP for an automatic address.
```
networksetup -getinfo Wi-Fi
```

How to fix it

Renew the DHCP lease. Choose Apple menu > System Settings > Network. Click the service, then click Details.
Click TCP/IP, then click Renew DHCP Lease. Click OK.
If Configure IPv4 is Manually, set it to Using DHCP, or use this command.
```
networksetup -setdhcp Wi-Fi
```
Needs an administrator password.
Restart the router. Then renew the lease again.
For Ethernet, try another cable, port or adapter.
Turn off security software for a test. If DHCP then works, examine its settings.

With Kilobat

kilobat diagnose checks the router and the internet, and gives advice when the router does not answer.
```
kilobat diagnose
```

Questions

Is a 169.254 address always bad?

No. Two Macs on one cable can talk with link-local addresses. But it does not reach the internet.

Will the Mac try DHCP again by itself?

Yes, it keeps trying. Renew the lease to try at once.

Sources

ipconfig(8), man page installed with macOS 27.2
Apple Support: Renew your IP address from the DHCP server on Mac
Apple Support: Change TCP/IP settings on Mac
RFC 3927: Dynamic Configuration of IPv4 Link-Local Addresses

Sources checked on 29 October 2026. Man pages are the ones installed with macOS; open one with man <name> in Terminal.