Configure static routes on dedicated servers

Static routing is a type of routing where routes are explicitly defined when configuring a network interface on a server or router.

To configure static routing, specify static routes on the server.

Examples of tasks that can be solved using static routing:

• connect dedicated servers and a cloud server via a private network.

Specify static routes on a server

Ubuntu

1. Connect to the server.

2. Open the network interfaces configuration file with the vi text editor:

   vi /etc/netplan/01-netcfg.yaml

3. At the end of the block with the parameters for the required network interface, add the route:

   routes:
   - to:  <ip_address>/<mask>
     via: <gateway>

   Specify:

   • <ip_address> — the subnet to which a route is needed;
   • <mask> — the subnet mask to which a route is needed;
   • <gateway> — the gateway for the current server's subnet, such as the gateway specified on the global router. The gateway address must be in the same subnet as the server.

4. If you need to specify multiple routes, add them sequentially in the same block, for example:

   routes:
   - to:  192.168.0.0/28
     via: 192.168.0.1
   - to:  192.168.1.0/28
     via: 192.168.0.1

5. Exit the vi text editor saving your changes:

   :wq

6. Check the route configuration:

   sudo netplan try

7. Apply the changes:

   netplan apply

Debian

1. Connect to the server.

2. Open the network interfaces configuration file with the vi text editor:

   vi /etc/network/interfaces.d/50-cloud-init

3. At the end of the block with the parameters of the corresponding network interface, add the required route:

   up route add -net <ip_address> netmask <mask> gw <gateway>
   down route del -net <ip_address> netmask <mask> gw <gateway>

   Specify:

   • <ip_address> — the subnet to which a route is needed, for example, 192.168.0.0;
   • <mask> — the subnet mask to which a route is needed, for example, 255.255.255.0;
   • <gateway> — the gateway for the current server's subnet, such as the gateway specified on the global router. The gateway address must be in the same subnet as the server

4. If you need to specify multiple routes, add them sequentially in the same block.

5. Exit the vi text editor saving your changes:

   :wq

6. Restart the network:

   sudo /etc/init.d/networking restart

CentOS

1. Connect to the server.

2. Create and fill in a file to configure static routes:

   echo "<ip_address>/<mask> via <gateway>" >> /etc/sysconfig/network-scripts/route-<eth_name>

   Specify:

   • <ip_address> — the subnet to which a route is needed;
   • <mask> — the subnet mask to which a route is needed;
   • <gateway> — the gateway for the current server's subnet, such as the gateway specified on the global router. The gateway address must be in the same subnet as the server;
   • <eth_name> — the name of the corresponding LAN interface.

3. If you need to add several routes, specify them in a single command. Start each route on a new line, for example:

   echo "192.168.0.0/28 via 172.16.0.1
   192.168.1.0/28 via 172.16.0.1" >> /etc/sysconfig/network-scripts/route-eno2

4. Restart the network:

   systemctl restart network

Windows

1. Connect to the server via RDP or using the KVM console.

2. Add the required routes one by one:

   route -p ADD <ip_address> MASK <mask> <gateway> METRIC <x>

   Specify:

   • <ip_address> — the subnet to which a route is needed, for example, 192.168.0.0;
   • <mask> — the subnet mask to which a route is needed, for example, 255.255.255.0;
   • <gateway> — the gateway for the current server's subnet, such as the gateway specified on the global router. The gateway address must be in the same subnet as the server;
   • <x> — a parameter that specifies the priority of the defined gateway, 1 being the highest priority.

Example of organizing static routes to connect dedicated servers and a cloud server via a private network

Configuration goal

Connect two dedicated servers in the SPB-2 pool and a cloud server in the ru-2 pool with a private network using a global router, and configure routing in the network so that the devices can see each other.

What you need for configuration

In the configuration example, we used two dedicated servers in the SPB-2 pool with access to a private network and a cloud server in the ru-2 pool.

Configuration result

Private connectivity will be configured between two dedicated servers in the SPB-2 pool and a cloud server in the ru-2 pool.

Configuration steps

1. Create a global router.

2. Connect private subnets to the global router:

   • 192.168.0.0/28 for the VLAN containing the dedicated servers in the SPB-2 pool;
   • 172.16.0.0/28 for the cloud platform project in the ru-2 pool.

3. Assign IP addresses from the private subnets you connected to the global router to the dedicated servers and the cloud server. For more details, see the Assigning IP addresses to servers subsection.

4. Specify routes:

   • on each dedicated server in the SPB-2 pool — to the 172.16.0.0/28 subnet through gateway 192.168.0.1;
   • on the cloud server in the ru-2 pool — to the 192.168.0.0/28 subnet through gateway 172.16.0.1.