Internet Connection Sharing: Difference between revisions
imported>Onny Init instruction share connection via ethernet |
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sudo create_ap wlan0 eth0 MyAccessPoint | sudo create_ap wlan0 eth0 MyAccessPoint | ||
</syntaxhighlight> | </syntaxhighlight> | ||
Here <code>eth0</code> is the ethernet interface connected to the internet, and <code>wlan0</code> is the wifi interface to share the internet connection with a wifi hotspot. However, these names may not be the same on your system. To check the name of your hardware interface use the command <code>ifconfig</code> or <code>ifconfig | grep ^[^:]*:</code> It will list network adapters on your system. Then modify command accordingly <code>sudo create_ap <wifiInterfaceName> <ethernetInterfaceName> MyAccessPoint <Password></code> | |||
=== Configuration === | === Configuration === | ||
Persistently share an existing internet connection of a wired interface <code>eth0</code> using a wifi hotspot on <code>wlan0</code> with the access point name <code>My Wifi Hotspot</code>. The network is protected with a simple WPA2 pre-shared key <code>12345678</code>. | |||
<syntaxhighlight lang="nix"> | <syntaxhighlight lang="nix"> | ||
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</syntaxhighlight> | </syntaxhighlight> | ||
== Share via ethernet == | |||
=== Usage === | |||
Share an existing internet connection of a wireless interface <code>wlan0</code> to clients connected on a ethernet device <code>eth0</code>. | Share an existing internet connection of a wireless interface <code>wlan0</code> to clients connected on a ethernet device <code>eth0</code>. Make sure you've got TCP and UDP port <code>53</code> for the dnsmasq DHCP server opened in your [[Firewall]]. | ||
<syntaxhighlight lang="bash"> | <syntaxhighlight lang="bash"> | ||
# Setup ethernet device | |||
ip link set up eth0 | ip link set up eth0 | ||
ip addr add 10.0.0.1 dev eth0 | ip addr add 10.0.0.1/24 dev eth0 | ||
# Enable packet forwarding | # Enable packet forwarding | ||
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# Enable NAT for leaving packets | # Enable NAT for leaving packets | ||
nft add table ip nat | |||
nft add chain ip nat POSTROUTING { type nat hook postrouting priority 100 \; } | |||
nft add rule nat POSTROUTING oifname wlan0 masquerade | |||
# Start dnsmasq for DHCP | # Start dnsmasq for DHCP | ||
dnsmasq -d -i eth0 - | dnsmasq -d -i eth0 --dhcp-range=10.0.0.2,10.0.0.255,255.255.255.0,24h | ||
</syntaxhighlight> | |||
To cleanup the configured interface run following commands | |||
<syntaxhighlight lang="bash"> | |||
ip addr del 10.0.0.1/24 dev eth0 | |||
ip link set down eth0 | |||
# Get handle_number with: nft -a list table nat | |||
nft delete rule nat POSTROUTING handle <handle_number> | |||
</syntaxhighlight> | |||
=== Configuration === | |||
Persistently share an existing internet connection on interface `wlan0` to clients connected on an ethernet interface `eth0`. Tested where `wlan0` is a wireless interface, but it should work with a different ethernet interface as well. You do not need to manually open port 53. | |||
<syntaxhighlight lang="nix"> | |||
# Set a static IP on the "downstream" interface | |||
networking.interfaces."eth0" = { | |||
useDHCP = false; | |||
ipv4.addresses = [{ | |||
address = "10.0.0.1"; | |||
prefixLength = 24; | |||
}]; | |||
}; | |||
networking.firewall.extraCommands = '' | |||
# Set up SNAT on packets going from downstream to the wider internet | |||
iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE | |||
# | # Accept all connections from downstream. May not be necessary | ||
iptables -A INPUT -i enp2s0 -j ACCEPT | |||
''; | |||
iptables - | # Run a DHCP server on the downstream interface | ||
services.kea.dhcp4 = { | |||
enable = true; | |||
settings = { | |||
interfaces-config = { | |||
interfaces = [ | |||
"eth0" | |||
]; | |||
}; | |||
lease-database = { | |||
name = "/var/lib/kea/dhcp4.leases"; | |||
persist = true; | |||
type = "memfile"; | |||
}; | |||
rebind-timer = 2000; | |||
renew-timer = 1000; | |||
subnet4 = [ | |||
{ | |||
id = 1; | |||
pools = [ | |||
{ | |||
pool = "10.0.0.2 - 10.0.0.255"; | |||
} | |||
]; | |||
subnet = "10.0.0.1/24"; | |||
} | |||
]; | |||
valid-lifetime = 4000; | |||
option-data = [{ | |||
name = "routers"; | |||
data = "10.0.0.1"; | |||
}]; | |||
}; | |||
}; | |||
</syntaxhighlight> | </syntaxhighlight> | ||
[[Category:Networking]] | [[Category:Networking]] |
Latest revision as of 10:14, 17 December 2024
The following example will describe how to share an active internet connection over a WiFi hotspot or alternatively via ethernet.
Usage
Share an existing internet connection of a wired interface eth0
using a wifi hotspot on wlan0
with the access point name MyAccessPoint
.
nix shell nixpkgs#linux-wifi-hotspot
sudo create_ap wlan0 eth0 MyAccessPoint
Here eth0
is the ethernet interface connected to the internet, and wlan0
is the wifi interface to share the internet connection with a wifi hotspot. However, these names may not be the same on your system. To check the name of your hardware interface use the command ifconfig
or ifconfig | grep ^[^:]*:
It will list network adapters on your system. Then modify command accordingly sudo create_ap <wifiInterfaceName> <ethernetInterfaceName> MyAccessPoint <Password>
Configuration
Persistently share an existing internet connection of a wired interface eth0
using a wifi hotspot on wlan0
with the access point name My Wifi Hotspot
. The network is protected with a simple WPA2 pre-shared key 12345678
.
services.create_ap = {
enable = true;
settings = {
INTERNET_IFACE = "eth0";
WIFI_IFACE = "wlan0";
SSID = "My Wifi Hotspot";
PASSPHRASE = "12345678";
};
};
Usage
Share an existing internet connection of a wireless interface wlan0
to clients connected on a ethernet device eth0
. Make sure you've got TCP and UDP port 53
for the dnsmasq DHCP server opened in your Firewall.
# Setup ethernet device
ip link set up eth0
ip addr add 10.0.0.1/24 dev eth0
# Enable packet forwarding
sysctl net.ipv4.ip_forward=1
# Enable NAT for leaving packets
nft add table ip nat
nft add chain ip nat POSTROUTING { type nat hook postrouting priority 100 \; }
nft add rule nat POSTROUTING oifname wlan0 masquerade
# Start dnsmasq for DHCP
dnsmasq -d -i eth0 --dhcp-range=10.0.0.2,10.0.0.255,255.255.255.0,24h
To cleanup the configured interface run following commands
ip addr del 10.0.0.1/24 dev eth0
ip link set down eth0
# Get handle_number with: nft -a list table nat
nft delete rule nat POSTROUTING handle <handle_number>
Configuration
Persistently share an existing internet connection on interface `wlan0` to clients connected on an ethernet interface `eth0`. Tested where `wlan0` is a wireless interface, but it should work with a different ethernet interface as well. You do not need to manually open port 53.
# Set a static IP on the "downstream" interface
networking.interfaces."eth0" = {
useDHCP = false;
ipv4.addresses = [{
address = "10.0.0.1";
prefixLength = 24;
}];
};
networking.firewall.extraCommands = ''
# Set up SNAT on packets going from downstream to the wider internet
iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE
# Accept all connections from downstream. May not be necessary
iptables -A INPUT -i enp2s0 -j ACCEPT
'';
# Run a DHCP server on the downstream interface
services.kea.dhcp4 = {
enable = true;
settings = {
interfaces-config = {
interfaces = [
"eth0"
];
};
lease-database = {
name = "/var/lib/kea/dhcp4.leases";
persist = true;
type = "memfile";
};
rebind-timer = 2000;
renew-timer = 1000;
subnet4 = [
{
id = 1;
pools = [
{
pool = "10.0.0.2 - 10.0.0.255";
}
];
subnet = "10.0.0.1/24";
}
];
valid-lifetime = 4000;
option-data = [{
name = "routers";
data = "10.0.0.1";
}];
};
};