Configure a Linux system as a wifi router or hotspot

This article provide a simple and precise steps to create a Wi-Fi Hotspot or router on Ubuntu / Debian / Fedora / CentOS / RHEL/ Arch Linux system using nmcli command line network management tool. If you don’t have a wifi router and you want to share internet connection to other folks through your laptop, this is the right article for you.

Topic

• How to configure a Linux system as a wifi router or hotspot?

• Setup Linux wifi hotspot

• Share internet through Linux wifi hotspot

• Configure Linux wifi hotspot on Ubuntu/Debian/Centos/Arch Linux/RHEL

• Configure Linux wifi router on Ubuntu/Debian/Centos/Arch Linux/RHEL

Prerequisites for Linux hotspot or wifi router

• Make sure your laptop or system has a active internet connection either through the LAN interface or through a USB dongle.

• For our testing I used a Airtel 4g dongle which provides internet connection to the laptop. If you have a active LAN internet you can use that too.

• Identify the wireless device name. In our case the device name is wlan0. You may have the device name as wlp*.

# ip link show|grep wl
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000

• Check whether the wireless device has support for access point(ap) mode. This ap mode is needed to setup the wifi interface as a wifi hotsopt or access point.

# iw list| grep -A 8 "Supported interface modes:"
    Supported interface modes:
         * IBSS
         * managed
         * AP <<<<<<<<<<<<<<<< Here
         * AP/VLAN
         * monitor
         * P2P-client
         * P2P-GO
         * P2P-device

• Make sure NetworkManager is enabled and working.

Linux Wifi router or hotspot configuration

• Create a profile for hotspot. Here hotspot or wifi name is LinsHotspot.

# WIFIINT="wlan0"
# WIFI_SSID="LinsHotspot"
# nmcli con add type wifi ifname $WIFIINT con-name $WIFI_SSID autoconnect yes ssid $WIFI_SSID

• Set wifi access point method as shared.

nmcli con modify $WIFI_SSID 802-11-wireless.mode ap 802-11-wireless.band bg ipv4.method shared

• Set your wifi hotspot security type(wpa-psk) and password.

# nmcli con modify $WIFI_SSID wifi-sec.key-mgmt wpa-psk
# nmcli con modify $WIFI_SSID wifi-sec.psk "type_pass_here"

• Bring up the hotspot connection.

# nmcli con up $WIFI_SSID

• Now check your connection status.

# nmcli connection show $WIFI_SSID

# nmcli connection show 
NAME          UUID                       TYPE       DEVICE    
Hostspot      fd3r1fc-dkjjjwe-oko12      wifi       wlan0 

• Now check the hotspot router or interface IP address.

3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 21:79:19:5e:3b:80 brd ff:ff:ff:ff:ff:ff
    inet 10.42.0.1/24 brd 10.42.0.255 scope global noprefixroute wlp6s0
       valid_lft forever preferred_lft forever
[...]

• By default wifi hotspot get 10.42.0.1 IP address and the network is 10.42.0.0/24. In the background NetworkManager runs a DHCP server through dnsmasq which will provide IP address to all wifi users from 10.42.0..0/24 network.

• Now scan the wifi hotspot on your mobile or laptop or any wifi supported device to connect to your hotspot. Upon scanning you will see hotspot name LinsHotspot.