Network Configuration in FreeBSD: Between DHCP, Static IP, and That Elusive Wi-Fi

 

If FreeBSD were a college student, network configuration would be how it says:
"Hey, I live here now, and this is my IP address."
Let’s help it not get lost every time it boots up! 

First Things First: Check Your Interface Name

Before anything, we need to know your network interface's name. In FreeBSD, interface names are often... creatively named (like neighborhood cats).

Use:

ifconfig

Sample output:

em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500

Here, em0 is the interface name. For Wi-Fi, it could be wlan0, ath0, iwn0, or other funky aliases.

DHCP: The Lazy, Chill Option

If you want FreeBSD to automatically request an IP from your router, just add this to /etc/rc.conf:

ifconfig_em0="DHCP"

Replace em0 with your actual interface name, of course.

Static IP: Loyal and Predictable

If you need a fixed IP address (e.g., for a local server), use this config in /etc/rc.conf:

ifconfig_em0="inet 192.168.1.100 netmask 255.255.255.0"
defaultrouter="192.168.1.1"

Explanation:

• 192.168.1.100: Your desired IP
• 255.255.255.0: Typical netmask
• 192.168.1.1: Your gateway/router

Wi-Fi: Internet That Needs Sweet Talking

Wi-Fi on FreeBSD can be... temperamental. But yes, it’s possible! Here’s how:

1. Load the Driver and Firmware

For example, if you're using Intel Wi-Fi:

kldload if_iwm
kldload iwm8265fw

Add them to /boot/loader.conf to auto-load at boot:

if_iwm_load="YES"
iwm8265fw_load="YES"

2. Create wpa_supplicant.conf

vi /etc/wpa_supplicant.conf

Contents:

network={
    ssid="YourWiFiName"
    psk="yourpassword"
}

3. Add to rc.conf

wlans_iwm0="wlan0"
ifconfig_wlan0="WPA DHCP"

Or if you want a static IP:

ifconfig_wlan0="WPA inet 192.168.1.150 netmask 255.255.255.0"
defaultrouter="192.168.1.1"

Restart the Network

After setting everything, restart with:

service netif restart
service routing restart

If using Wi-Fi:

service wpa_supplicant restart

Check Your Connection

Check your IP:

ifconfig

Test connectivity:

ping google.com

If you get replies, congratulations — your FreeBSD box just made contact with the outside world! 

Mode	Simplicity	Best For
DHCP	Easiest	Desktops & laptops
Static IP	Needs precision	Servers, Raspberry Pi
Wi-Fi + WPA	Needs effort	Laptops & DIY nerds