ifconfig en0Show the Wi-Fi interface (en0 on most Macs).
When to use it
Use ifconfig to see an interface's IPv4 and IPv6 addresses, MAC address, MTU and link status, or to see which virtual interfaces VPNs, Docker and Continuity have created.
Steps
List interfaces
A Mac has many: physical ports plus virtual ones.ifconfig -lShow one interface
Most details you need are in a few lines.ifconfig en0Find active interfaces
status: active means a link is up.ifconfig | grep -B8 'status: active' | grep '^[a-z]'Map names to ports
networksetup tells you which enX is Wi-Fi, Ethernet or Thunderbolt.networksetup -listallhardwareports
Output explained
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether a6:c7:2b:7c:db:e4
inet6 fe80::5f:daca:262:290f%en0 prefixlen 64 secured scopeid 0xe
inet 192.168.1.23 netmask 0xffffff00 broadcast 192.168.1.255
inet6 2001:db8:452b:8d00:dd9c:206e:79c:6f02 prefixlen 64 autoconf temporary
status: active
- flags UP and RUNNING: the interface is enabled and has a link. mtu 1500 is the standard Ethernet size.
- ether: the MAC address in use.
- inet / netmask: the IPv4 address and mask (0xffffff00 = /24).
- inet6 … temporary / deprecated: rotating privacy addresses; deprecated ones are being phased out.
Common interfaces: lo0 loopback, en0 Wi-Fi, en1–en9 Ethernet and Thunderbolt, utun0+ VPNs and system tunnels, awdl0 and llw0 AirDrop and Continuity, bridge100 Internet Sharing or virtual machines, anpi Apple USB-C network devices.
Options and variations
| Flag | Meaning | Example |
|---|---|---|
| -l | Interface names only | ifconfig -l |
| -a | All interfaces (default) | ifconfig -a |
| IF | One interface | ifconfig en0 |
| IF mtu N | Set MTU temporarily (sudo) | sudo ifconfig en0 mtu 1400 |
| IF down / up | Disable / enable an interface (sudo) | sudo ifconfig en0 down |
Common errors
| Error | Cause | Fix |
|---|---|---|
| Changes disappear | ifconfig changes aren't saved | Use System Settings or networksetup for permanent settings. |
| Lots of utun interfaces | macOS and VPN apps create tunnels | Normal; utun interfaces with no inet address are idle. |
Do it in the app
LightAtom shows connections whichever interface they use, including the VPN app's own connection to its server.
Frequently asked questions
Is ifconfig deprecated on Mac?
No. ifconfig is still included and works on macOS 15. For settings that persist, use networksetup or System Settings.
What is en0 on a Mac?
Usually the Wi-Fi interface. Check with networksetup -listallhardwareports, which lists each hardware port and its device name.
What is utun on a Mac?
A tunnel interface used by VPNs and system services (iCloud Private Relay, Back to My Mac's successors). Several utun interfaces are normal.