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, add static routes on the server.

Examples of tasks that can be solved using static routing:

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

Specify static routes on a server

Ubuntu

1. Connect to the server.

2. View the configuration file name of the netplan utility:

   ls /etc/netplan/

   The response will show the configuration file name. For example:

   01-netcfg.yaml

   Copy the configuration file name.

3. Open the configuration file of the netplan utility with the text editor vi:

   vi /etc/netplan/<file_name>

   Specify <file_name> — the configuration file name that you copied in step 2.

4. At the end of the block with parameters of the required network interface, add a route:

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

   Specify:

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

5. If you need to configure 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

6. Press ESC.

7. Exit the text editor vi saving changes:

   :wq

8. Check the route configuration:

   sudo netplan try

9. Apply the changes:

   netplan apply

Debian

1. Connect to the server.

2. View the configuration file name of the ifupdown utility:

   ls /etc/network/interfaces.d/

   The response will show the configuration file name. For example:

   50-cloud-init

   Copy the configuration file name.

3. Open the configuration file of the ifupdown utility with the text editor vi:

   vi /etc/network/interfaces.d/<file_name>

   Specify <file_name> — the configuration file name that you copied in step 2.

4. At the end of the block with parameters of the corresponding network interface, add a route:

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

   Specify:

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

5. If you need to configure multiple routes, add them sequentially in the same block.

6. Press ESC.

7. Exit the text editor vi saving changes:

   :wq

8. Restart the network:

   sudo /etc/init.d/networking restart

CentOS

1. Connect to the server.

2. Create and populate the static route configuration file:

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

   Specify:

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

3. If you need to add multiple routes, specify them in a single command. Specify 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 via the KVM console.

2. Add the required routes one by one:

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

   Specify:

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

Example of configuring static routes for connecting dedicated servers and a cloud server over a private network

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 communicate with each other.

Prerequisites

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.

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 to the VLAN where the dedicated servers in the SPB-2 pool are located;
   • 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 cloud server. For more information, see the Assign IP addresses to servers section.

4. Configure routes:

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