Connecting to a wireless access point

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This document describes how to set up a wireless network connection with WPA encryption.

First make sure your wireless drivers are loaded properly. (if you are using a Broadcom chipset, see the section at the bottom of this post.)

Install wireless-tools and wpa_supplicant.

apk add wireless-tools wpa_supplicant

Bring the link up so we can look for wireless networks. (An error here means you probably need extra drivers/firmware.)

ip link set wlan0 up

Find a network to connect to. Look for the ESSID. In this example we will use the ESSID "MyNet".

iwlist wlan0 scanning

Let's set the ESSID:

iwconfig wlan0 essid MyNet

We need to create a shared key for wpa_supplicant.

wpa_passphrase MyNet > wpa.conf

It will wait for the password from stdin. Enter the password and enter. Now you will have a wpa.conf file with the preshared key.

Start wpa_supplicant with the generated config:

wpa_supplicant -Dwext -iwlan0 -c ./wpa.conf

From another console, start dhcpcd:

udhcpc -i wlan0

You should get an IP address.

You then want to make the connection process automatic on boot-up. Open /etc/network/interfaces and add the following stanza:

auto wlan0
iface wlan0 inet dhcp
Note: I had to append `pre-up iwconfig wlan0 essid <ESSID>` to automatically connect to the network.

You will also need to set wpa_supplicant to start automatically on boot:

rc-update add wpa_supplicant boot

Next, create /etc/wpa_supplicant/ (permissions of 755 with root:root are fine), and move wpa.conf into that folder, renaming it to wpa_supplicant.conf.

Reboot and check that you are associated with the access point:

iwconfig wlan0

and check that you got a DHCP lease:

ifconfig wlan0 | grep addr

Broadcom Wi-Fi Chipset Users

The Broadcom chipset is quite popular among older computers. You will need to compile the firmware manually for this chipset as it is not included.

You can check if you have a Broadcom chipset by using dmesg:

dmesg | grep Broadcom

First install the SDK an Git:

apk add alpine-sdk git

Then git clone aports from git.alpinelinux.org.

(remove $, new users can't add links to the wiki)

git clone git:/$/git.alpinelinux.org/abuild

Change your directory to aports/non-free/b43-firmware, then build it.

You can't be root and must be a user of the group abuild (use groupadd)

abuild -r

Install the generated packge file (it will be in ~/packages/) - make sure to pass --allow-untrusted

apk add --allow-untrusted ~/packages/...pkg

Now we need fwcutter, which is executed from the firmware package:

apk add b43-fwcutter b43-firmware

Now you need to use modprobe so the device will show up:

modprobe b43

To automate this on startup add it to /etc/modules:

echo b43 >> /etc/modules

Now continue with the normal instructions.