====== Configure Wireless using wpa_supplicant for Odroid minimal image ======

Find the wireless card Interface name.

<code># iwconfig
sit0      no wireless extensions.

lo        no wireless extensions.

eth0      no wireless extensions.

ip6tnl0   no wireless extensions.

wlx40a5efd52a6d  unassociated  Nickname:"<WIFI@REALTEK>"
          Mode:Auto  Frequency=2.412 GHz  Access Point: Not-Associated
          Sensitivity:0/0
          Retry:off   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=0/100  Signal level=0 dBm  Noise level=0 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0</code>

Need to append the **net.ifnames=0** to **bootargs**  in **/media/boot/boot.ini** to change the interface name to wlan0.


Following are the steps to Create wireless service to connect to your router.

**Step1 : Find SSID to connect.**
<code>
# sudo iwlist wlan0 scanning | egrep 'Cell |Encryption|Quality|Last beacon|ESSID'
          Cell 01 - Address: 5E:CF:7F:84:54:70
                    ESSID:"smartpower2"
                    Encryption key:on
                    Quality=0/100  Signal level=-45 dBm
          Cell 02 - Address: 5E:CF:7F:13:91:D6
                    ESSID:"smartpower2"
                    Encryption key:on
                    Quality=0/100  Signal level=-45 dBm
          Cell 03 - Address: 2C:30:33:5E:8C:9D
                    ESSID:"MYSSID"
                    Encryption key:on
                    Quality=0/100  Signal level=-45 dBm
          Cell 04 - Address: 2C:30:33:5E:8C:9C
                    ESSID:"GoToHell-5G"
                    Encryption key:on
                    Quality=0/100  Signal level=-45 dBm
</code>

**Step2: Generate wireless wpa_supplicant configuration file**

This connection method allows quickly connecting to a network whose SSID is already known

<code># wpa_passphrase MY_SSID MY_PASSWORD > /etc/wpa_supplicant/wpa_supplicant.conf</code>

Replace **MY_SSID** with the actual network name, and replace **MY_PASSWORD** with the actual security key for the network. 

**Step3: Create Wireless Service file. /etc/systemd/system/network-wireless@.service**
Append the following to the service file

<code>
[Unit]
Description=Wireless network connectivity (%i)
Wants=network.target
Before=network.target
BindsTo=sys-subsystem-net-devices-%i.device
After=sys-subsystem-net-devices-%i.device

[Service]
Type=oneshot
RemainAfterExit=yes

ExecStart=/sbin/ip link set dev %i up
ExecStart=/sbin/wpa_supplicant -B -i %i -c /etc/wpa_supplicant/wpa_supplicant.conf
ExecStart=/sbin/dhclient %i

ExecStop=/sbin/ip link set dev %i down

[Install]
WantedBy=multi-user.target
</code>

Note: depend on you setting in your image you need to update the absolute patch for **ip, wpa_supplicant** and **dhclient** command

**Step4 : Need to Create Symbolic link to update the service.**

<code># ln -s /etc/systemd/system/network-wireless@.service /etc/systemd/system/multi-user.target.wants/network-wireless@wlan0.service</code>

**Step5 : Enable the service.**

<code># systemctl enable network-wireless@wlan0.service</code>

**Step6:  Reload the all the serivce** 

<code># systemctl daemon-reload</code>
**
Step7: Start the systemctrl service** 

<code># systemctl start network-wireless@wlan0.service</code>

**After this we will get ip address from the router.**

<code># ifconfig
eth0      Link encap:Ethernet  HWaddr 00:1e:06:10:dc:ad
          inet addr:10.0.0.138  Bcast:10.0.0.255  Mask:255.255.255.0
          inet6 addr: fe80::21e:6ff:fe10:dcad/64 Scope:Link
          inet6 addr: 2002:ac10:e33c:e472:21e:6ff:fe10:dcad/64 Scope:Global
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:6808 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3519 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:7876906 (7.8 MB)  TX bytes:298180 (298.1 KB)
          Interrupt:40

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:160 errors:0 dropped:0 overruns:0 frame:0
          TX packets:160 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:11840 (11.8 KB)  TX bytes:11840 (11.8 KB)

wlan0     Link encap:Ethernet  HWaddr 40:a5:ef:d5:2a:6d
          inet addr:10.0.0.111  Bcast:10.0.0.255  Mask:255.255.255.0
          inet6 addr: 2002:ac10:e33c:e472:42a5:efff:fed5:2a6d/64 Scope:Global
          inet6 addr: 2002:ac10:e33c:e472:c056:d96b:b7f9:4425/64 Scope:Global
          inet6 addr: fe80::42a5:efff:fed5:2a6d/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:13 errors:0 dropped:0 overruns:0 frame:0
          TX packets:10 errors:0 dropped:1 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2830 (2.8 KB)  TX bytes:1700 (1.7 KB)</code>