Connect Scaleway Dedibox to Scaleway Elements

• tunnel
• gre
• dedibox
• instance

GRE tunnel - Overview

A GRE tunnel allows you to connect Scaleway Elements Instances with Scaleway Dedibox dedicated servers and vice versa to exchange files over a virtual network connection that passes through the public Internet.

The Generic Routing Encapsultion (GRE) protocol is designed as a tunneling tool in order to carry any OSI Layer 3 protocol over an IP network. It creates a point-to-point connection like a virtual private network (VPN) but without adding lots of latency or overhead.

Setting up the tunnel on a Scaleway Elements Instance

1. Connect to the Cloud Instance via SSH:

   ssh root@your-instance-ip
   Copy code

2. Create a new file called configure-tunnel.sh:

   touch /opt/configure-tunnel.sh
   Copy code

3. Open the file in a text editor and copy the following code into it (ensure that you relplace the IP as stated):

   nano /opt/configure-tunnel.sh
   Copy code

   #!/bin/bash
   
   REMOTE_IP="123.123.123.123" #Change this value to the public IP address of the Instance
   LOCAL_IP=`scw-metadata | grep "PRIVATE_IP=" | grep -oE '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+'`
   
   ip tunnel add tun1 mode gre remote $REMOTE_IP local $LOCAL_IP ttl 255
   ip addr add 192.168.0.1 dev tun1
   ip link set tun1 up
   ip route add 192.168.1.0/24 dev tun1
   echo "Tunnel configured."
   Copy code

4. Save the file, exit the text editor and make it executable:

   chmod +x /opt/configure-tunnel.sh
   Copy code

5. Run the script:

   /opt/configure-tunnel.sh
   Copy code

Setting up the tunnel on a Dedibox Server

1. Connect to the Dedibox dedicated server via SSH:

   ssh username@your-server-ip
   Copy code

2. Create a new file called configure-tunnel.sh:

   sudo touch /opt/configure-tunnel.sh
   Copy code

3. Open the file in a text editor and copy the following code into it (ensure that you relplace the IPs as stated):

   sudo nano /opt/configure-tunnel.sh
   Copy code

   #!/bin/bash
   
   REMOTE_IP="123.123.123.123" #Change this value to the public IP address of the Scaleway Cloud Instance
   LOCAL_IP="123.123.123.123" #Change this value to the public IP address of the Dedibox dedicated server
   
   ip tunnel add tun1 mode gre remote $REMOTE_IP local $LOCAL_IP ttl 255
   ip addr add 192.168.1.1 dev tun1
   ip link set tun1 up
   ip route add 192.168.0.0/24 dev tun1
   echo "Tunnel configured."
   Copy code

4. Save the file, exit the text editor and make it executable:

   sudo chmod +x /opt/configure-tunnel.sh
   Copy code

5. Run the script:

   sudo /opt/configure-tunnel.sh
   Copy code

Testing the tunnel

1. Run a first test by pinging the other endpoint to see if the tunnel is working:

   username@dedibox:~# ping 192.168.0.1
   PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.
   64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=0.854 ms
   64 bytes from 192.168.0.1: icmp_seq=2 ttl=64 time=1.67 ms
   64 bytes from 192.168.0.1: icmp_seq=3 ttl=64 time=0.854 ms
   64 bytes from 192.168.0.1: icmp_seq=4 ttl=64 time=0.651 ms
   --- 192.168.0.1 ping statistics ---
   4 packets transmitted, 4 received, 0% packet loss, time 2999ms
   rtt min/avg/max/mdev = 0.651/1.007/1.670/0.392 ms
   Copy code

   root@scw-instance:~# ping 192.168.1.1
   PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
   64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=1.22 ms
   64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=1.01 ms
   64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=1.17 ms
   64 bytes from 192.168.1.1: icmp_seq=4 ttl=64 time=1.10 ms
   --- 192.168.1.1 ping statistics ---
   4 packets transmitted, 4 received, 0% packet loss, time 3004ms
   rtt min/avg/max/mdev = 1.011/1.130/1.226/0.084 ms
   Copy code

2. Install a web server on the Dedibox:

   sudo apt update && sudo apt install nginx -y
   Copy code

3. Enter the directory that is used to serve websites:

   cd /var/www/html
   Copy code

4. Download a test file into the /var/www/html directory:

   sudo wget http://ping.online.net/1000Mo.dat
   Copy code

5. Install curl on the Instance:

   apt update && apt install curl -y
   Copy code

6. Run a bandwidth test with curl:

   root@scw-instance:~# curl -4 -o /dev/null http://192.168.1.1/1000Mo.dat
     % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                   Dload  Upload   Total   Spent    Left  Speed
   100  953M  100  953M    0     0  97.8M      0  0:00:09  0:00:09 --:--:-- 67.0M
   Copy code

As you can see in the example above, the tunnel creates very low overhead and the bandwidth available for the Instance can be used.

Configuring an Automatic Start of the Tunnel on System Boot

1. Create a systemd script in the directory /etc/systemd/system, called configure-tunnel.service, and open it in a text editor:

   nano /etc/systemd/system/configure-tunnel.service
   Copy code

2. Copy/paste the following content into the file:

   [Unit]
   After=network.target
   
   [Service]
   ExecStart=/opt/configure-tunnel.sh
   
   [Install]
   WantedBy=default.target
   Copy code

3. Save the file and exit the text editor.

4. Set the file permissions, reload the systemd daemon and enable the newly created service:

   chmod 664 /etc/systemd/system/configure-tunnel.service
   systemctl daemon-reload
   systemctl enable configure-tunnel.service
   Copy code

   On the next reboot systemd will run the script during the boot process to automatically configure the tunnel.

Going further

Scaleway provides a wide range of Dedibox dedicated servers, with options such as Private Network, RPN-SAN, Backup, Monitoring.

You can use the virtual network you just set up to communicate between your Scaleway Elements Instances, Bare Metal Servers and your Dedibox dedicated servers over a virtual network connection. This can be useful to configure services like databases that are not available on the public network and use the virtual connection to communicate between them.