Setting up an OpenConnect Server on Arch Linux for VPN Connections
In this article, we will go through the process of setting up an OpenConnect server on Arch Linux for secure VPN connections. OpenConnect is an open-source VPN client that is compatible with the Cisco AnyConnect VPN protocol. It is a popular choice for those looking for a secure and flexible VPN solution.
Prerequisites
Before we begin, make sure you have the following:
- A server running Arch Linux
- Root or sudo access to the server
Installing OpenConnect
To install OpenConnect on Arch Linux, run the following command:
# pacman -S openconnect
Configuring OpenConnect
Once OpenConnect is installed, we need to create a new configuration file. Run the following command to create a new file called ocserv.conf.
# nano /etc/ocserv/ocserv.conf
Here is an example configuration file:
# /etc/ocserv/ocserv.conf
# Server configuration
server-host=0.0.0.0
server-port=8443
# Certificate and private key
certificate=/etc/ocserv/ocserv.cert
private-key=/etc/ocserv/ocserv.key
# Authentication
auth=plain
username=user
password=password
# Network settings
netmask-len=24
dhcp-range=192.168.2.2,192.168.2.254
# Logging
log-file=/var/log/ocserv.log
log-level=debug
Make sure to replace user and password with your own values. You can also generate a new certificate and private key using the following command:
# openssl req -x509 -nodes -newkey rsa:4096 -keyout /etc/ocserv/ocserv.key -out /etc/ocserv/ocserv.cert -days 3650 -subj "/CN=ocserv"
Setting up the VPN Interface
Next, we need to add a new network interface for the VPN. Run the following command to create a new file called vpn.network.
# nano /etc/systemd/network/vpn.network
Here is an example network file:
# /etc/systemd/network/vpn.network
[Match]
Name=vpn0
[Network]
Address=192.168.2.1/24
DHCPServer=yes
Once the network file is created, enable and start the network service:
# systemctl enable systemd-networkd
# systemctl start systemd-networkd
Adding Firewall Rules
Next, we need to add firewall rules to allow traffic to the OpenConnect server. Run the following commands to add the rules:
# iptables -A INPUT -p tcp --dport 22 -j ACCEPT
# iptables -A INPUT -p tcp --dport 8443 -j ACCEPT
# iptables-save | systemd-tmpfiles --create --prefix /etc/iptables/
Starting the OpenConnect Server
Finally, start the OpenConnect server using the following command:
# systemctl start ocserv
Connecting to the VPN
To connect to the VPN, use the OpenConnect client and specify the server address and port:
$ openconnect -u user --passwd password 192.168.2.1:8443
In this article, we have gone through the process of setting up an OpenConnect server on Arch Linux for secure VPN connections. We have covered the following:
- Installing OpenConnect
- Configuring OpenConnect
- Setting up the VPN interface
- Adding firewall rules
- Starting the OpenConnect server
- Connecting to the VPN