Setup WiFi
After you have connected a WiFi device, either using the Wireless/uSD pin on the MistyCarrier or plugging a supported WiFi adapter into the USB port, you can manually bring up the device with ifconfig wlan0 up. Confirm with ifconfig that your device is up:
# ifconfig
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:96 errors:0 dropped:0 overruns:0 frame:0
TX packets:96 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:6048 (5.9 KiB) TX bytes:6048 (5.9 KiB)
wlan0 Link encap:Ethernet HWaddr 18:A6:F7:0A:65:2D
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Scan Access Points
In case you want to scan for every WiFi access point in your environment, you can use the command below to list their SSIDs:
iw wlan0 scan | egrep -w "signal:|SSID:" | paste -d ' ' - - | sort
If your WiFi module is working correctly, the output of the command above should be similar to this:
signal: -42.00 dBm SSID: MistyWest
signal: -43.00 dBm SSID: MistyDeploy
signal: -43.00 dBm SSID: MistyGuest
signal: -60.00 dBm SSID: TELUS1924
signal: -64.00 dBm SSID: TELUSE55B
signal: -70.00 dBm SSID: TELUSB840
signal: -71.00 dBm SSID: SHAW-714340
Configuration
To connect to a specific WiFi access point, you need to provide the wpa_supplicant with the SSID and its passphrase using the command below:
mkdir /etc/wpa_supplicant
wpa_passphrase {YOUR-SSID} {YOUR-PASSPHRASE} > /etc/wpa_supplicant/wpa_supplicant-wlan0.conf
The newly created wpa_supplicant-wlan0.conf file will look like this:
network={
ssid="{YOUR-SSID}"
#psk="{YOUR-PASSPHRASE}"
psk={64-hash-characters}
}
In case you are using WPA-Enterprise or other advanced configuration, see the wpa_supplicant.conf(5) examples and modify the file accordingly.
Connect
After the configuration file is ready, enable the two services below to connect to the SSID on each boot automatically:
systemctl enable --now wpa_supplicant@wlan0
Need Other Services to Run After WiFi is Connected?
Every service file with the parameter After=network-online.target will run after the WiFi is connected and an IP address is acquired.
Need a Static IP?
You will most likely be using a dynamic IP address and the DHCP client service obtains the IP per each connection. In case you want to use a static IP, create or edit the /etc/dhcpcd.conf file. For example:
interface wlan0
static ip_address=192.168.1.10/24
static routers=192.168.1.1
static domain_name_servers=192.168.1.1 8.8.8.8
More complicated configurations are possible, for example, combining with the arping option. See dhcpcd.conf(5) for details.
A restart will be required for the new configuration to work.
Check Connection
To check if you are on a working connection, you can check the output of iw wlan0 link command:
Connected to 62:22:32:28:53:7e (on wlan0)
SSID: MW (Limited MAC)
freq: 5200
RX: 1028880 bytes (6289 packets)
TX: 495655879 bytes (355731 packets)
signal: -82 dBm
rx bitrate: 6.0 MBit/s
tx bitrate: 27.0 MBit/s
bss flags:
dtim period: 3
beacon int: 100
To make sure your wlan0 device obtained a correct IP, you can check the output of ip a command:
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
2: can0: <NOARP40000> mtu 72 qdisc noop qlen 10
link/[280]
3: can1: <NOARP40000> mtu 72 qdisc noop qlen 10
link/[280]
4: eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop qlen 1000
link/ether 06:87:9a:a2:e3:4f brd ff:ff:ff:ff:ff:ff
5: eth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop qlen 1000
link/ether a2:69:d7:df:09:5d brd ff:ff:ff:ff:ff:ff
6: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue qlen 1000
link/ether 18:a6:f7:0a:65:2d brd ff:ff:ff:ff:ff:ff
inet 192.168.1.10/24 brd 192.168.9.255 scope global dynamic wlan0 <------------- This line should exist
valid_lft 560sec preferred_lft 271sec
Additionally, the ping mistywest.com command should show you that the domain name is resolved to a destination IP and you should receive responses once per second:
PING mistywest.com (172.67.213.204): 56 data bytes
64 bytes from 172.67.213.204: seq=0 ttl=59 time=27.031 ms
64 bytes from 172.67.213.204: seq=1 ttl=59 time=20.089 ms
64 bytes from 172.67.213.204: seq=2 ttl=59 time=17.214 ms
64 bytes from 172.67.213.204: seq=3 ttl=59 time=22.551 ms
Power Saving
By default, many WiFi modules, including the module on MistyCarrier, use an active power-saving configuration. To check the status of this configuration you can use the command below:
iw wlan0 get power_save
To disable the power saving temporarily, you can run the command below:
iw wlan0 set power_save off
If you want to make this setting permanent, you can create a service in /lib/systemd/system/wifi_powersave@.service with the content:
[Unit]
Description=Set WiFi power save %i
After=sys-subsystem-net-devices-wlan0.device
[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/usr/sbin/iw dev wlan0 set power_save %i
[Install]
WantedBy=sys-subsystem-net-devices-wlan0.device
Then you can enable the service with systemctl enable wifi_powersave@off.service
Troubleshooting
-
The Wifi connection is unstable or slow compared to your other devices?
-
Check if you are using a different frequency with
iw wlan0 link. Different frequencies cover different ranges. For example, maybe other devices are using 2.4GHz frequency while your device is using 5GHz frequency which is faster but less stable in further distances. -
It might be because of the power saving. See the section below to turn it off and see if it improves your connection.
-