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Configuring an internal IP-addresses on a Linux VPS

Once you have added your VPSs to a Private Network, you will first have to set up internal IP addresses before you can make full use of them.

In the examples, the 192.168.0.0/16 range is used. However, you can choose one of the IP ranges defined in the RFC for use within private networks: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. The examples also use nano as an editor, but you are free to use your favorite editor.

This article covers various Linux OS's. For Windows, please see this article.

  • Perform the steps in this article as root, or user with sudo rights.
     
  • In case of incorrect adjustments, you can make your VPS unreachable. Make sure you also have access to your VPS using the console in the control panel (if you do this via SSH). In addition, it is strongly recommended to make a Snapshot in advance which you can fall back on.

Fast Installs

 

Please note: Did you use our fast installs feature for VPS and chose installation via SSH-keys, one time password, or cloud-config user data? Additional steps are required before configuring the IP address for your private network connection.

Fast Installs uses Cloud Init. Cloud Init automatically overwrites your network configuration and for this reason Clud Init, or the Cloud Init control over your network (you're free to choose either option), needs to be disabled as follows:

 

Step 1

 

Disabling Cloud Init network management

Open/create the following file:

nano /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg

Add the contents below and then save and close the file (ctrl + x > y > enter).

network: config: disabled 

 

Disabling Cloud Init

Cloud Init is only used during the initial installation process of your VPS. As such, it doesn't hurt to disable it altogether. This can be done by creating the following empty file:

touch /etc/cloud/cloud-init.disabled

 

Step 2 - Ubuntu / Debian additional steps

In case of Ubuntu / Debian additional steps are recommended: In order to avoid confusion in the future, you can rename the network configuration file as made by Cloud Init to 01-netcfg.yaml using the command:

mv /etc/netplan/50-cloud-init.yaml /etc/netplan/01-netcfg.yaml

You can now proceed with the configuration of the IP address for your private network. Should Cloud Init still control your network configuration, you may additionally need to use the following command:

dpkg-reconfigure cloud-init

AlmaLinux 8

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2

Check the name of your private network adapter. This can be done using the command:

ip a

You'll see output similar to the example below. In this example the private network adapter is called eth1 (eth0 is the public adapter).

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:bb:ae:2c brd ff:ff:ff:ff:ff:ff
    inet 136.144.231.47/24 brd 136.144.231.255 scope global dynamic noprefixroute eth0
       valid_lft 84992sec preferred_lft 84992sec
    inet6 2a01:7c8:d005:298:5054:ff:febb:ae2c/64 scope global dynamic mngtmpaddr
       valid_lft 2591969sec preferred_lft 604769sec
    inet6 fe80::5054:ff:febb:ae2c/64 scope link
       valid_lft forever preferred_lft forever
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:c3:4e:be brd ff:ff:ff:ff:ff:ff
    inet6 fe80::4efd:854e:cbde:1676/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

 

Step 3

Open your network configuration file, or create it if it doesn't exist: 

nano /etc/sysconfig/network-scripts/ifcfg-eth1

 

Step 4

Add the options below / adjust the existing configuration. Replace the IP behind 'IPADDR' with the IP address that you actually want to use.

DEVICE=eth1
ONBOOT=yes
NETBOOT=yes
BOOTPROTO=static
IPADDR=192.168.1.2
NETMASK=255.255.255.0
ZONE=public 
USERCTL=no

 

Step 5

Save your settings and close your editor (ctrl + x > y > enter).

Finally, run the following command to restart the network: 

ifdown eth1 && ifup eth1

 

Optional: extra private IPs

If you want to set up more internal IPs, expand the configuration in step 3 with IPADDR1, IPADDR2, etc. and NETMASK1, NETMASK2, etc.: 

DEVICE=eth1
ONBOOT=yes 
NETBOOT=yes
BOOTPROTO=static 
IPADDR=192.168.1.2 
IPADDR1=192.168.1.3 
NETMASK=255.255.255.0 
NETMASK1=255.255.255.0 
ZONE=public
USERCTL=no

CentOS 7

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2

Check the name of your private network adapter. This can be done using the command:

ip a

You'll see output similar to the example below. Your MacAdress can be  Je MacAddres is shown like in the example encircled in red. Please note that you write down the MacAddress for eth1 and not eth0.

centos 7 ip a output


 

Step 3

Open your network configuration file, or create it if it doesn't exist: 

nano /etc/sysconfig/network-scripts/ifcfg-eth1

(eth1 is the name of your private network adapter. ifcfg-eth0 is the adapter of your public network.)   


 

Step 4

Add the options below / adjust the existing configuration. Replace the IP behind 'IPADDR' with the IP address that you actually want to use.

Do not adjust the values ​​behind HWADDR, UUID, etc. if you have an existing configuration!

DEVICE=eth1
ONBOOT=yes
NETBOOT=yes
BOOTPROTO=static
IPADDR=192.168.1.2
NETMASK=255.255.255.0
ZONE=public

 

Step 5

Save your settings and close your editor (ctrl + x > y > enter).

Finally, run the following command to restart the network: 

systemctl restart network

 

Optional: extra private IPs

If you want to set up more internal IPs, expand the configuration in step 3 with IPADDR0, IPADDR1, etc. and NETMASK0, NETMASK1, etc.: 

DEVICE=eth1
ONBOOT=yes 
NETBOOT=yes
BOOTPROTO=static 
IPADDR=192.168.1.2 
IPADDR0=192.168.1.3 
NETMASK=255.255.255.0 
NETMASK0=255.255.255.0 
ZONE=public

CentOS 8

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2

Check the name of your private network-adapter with the command:

ip a

Most commonly it will be called ens7:

ipa centos8 ens7

centos 7 ip a output


 

Step 3

Open your network configuration file, or create it if it doesn't exist: 

nano /etc/sysconfig/network-scripts/ifcfg-ens7

(ens7 is the name of your private network adapter. ens3 is the adapter of your public network.)   


 

Step 4

Add the options below / adjust the existing configuration. Replace the IP behind 'IPADDR' with the IP address that you actually want to use.

Do not adjust the values ​​behind HWADDR, UUID, etc. if they exist in your configuration.

DEVICE=ens7
ONBOOT=yes
NETBOOT=yes
BOOTPROTO=static
IPADDR=192.168.1.2
NETMASK=255.255.255.0
ZONE=public

 

Step 5

Save your settings and close your editor (ctrl + x > y > enter). Finally, run the following command to restart the network:

nmcli networking off
nmcli networking on

For the first internal IP you can also use systemctl restart NetworkManager. Any additional IP's require nmcli (the NetworkManager CLI client) using the commands above.


 

Optional: extra private IPs

If you want to set up more internal IPs, expand the configuration in step 3 with IPADDR1, IPADDR2, etc. and NETMASK1, NETMASK2, etc.: 

DEVICE=eth1
ONBOOT=yes 
NETBOOT=yes
BOOTPROTO=static 
IPADDR=192.168.1.2 
IPADDR1=192.168.1.3 
NETMASK=255.255.255.0 
NETMASK1=255.255.255.0 
ZONE=public

Debian 8 

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2 Open the network configuration: 

nano /etc/network/interfaces

 

Step 3 

Choose an internal IP address that you want to use and enter the following configuration at the bottom of the file (i.e. under the existing configuration): 

auto eth1
iface eth1 inet static
address 192.168.1.2
   netmask 255.255.255.0 

The configuration for eth0 is already included in the file. By adding the above code, you configure your private network adapter eth1 with a static IP address. 


 

Step 4

Save your settings and close your editor (ctrl + x > y > enter). Finally, run the following command to restart the network: 

systemctl restart networking

 

Optional: extra private IPs 

If you want to set up more internal IPs, you do this the same way as when you add extra regular IP addresses (you use this format per IP, so a third IP gets the interface name eth1:1, a fourth eth1:2 etc.): 

auto eth1:0
allow-hotplug eth1:0
iface eth1:0 inet static
   address 192.168.1.3
   netmask 255.255.255.0  

Debian 9

 

At the moment of writing, there is no accurate documentation from Debian itself about adding internal IP addresses in Debian 9.

The steps below require a reboot. Other options like service networking restart or ifdown ens3 && ifup ens3 make your IP addresses unreachable. Once Debian has updated its documentation for Debain 9, we will also adjust this in our documentation.

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2 

Open your network configuration:

nano /etc/network/interfaces

 

Step 3 

Add the configuration for ens7 at the bottom of the open file. 

auto ens7
iface ens7 inet static
   address 192.168.1.2
   netmask 255.255.255.0 

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 


 

Step 4 

Save your settings and close your editor (ctrl + x > y > enter). Finally, restart your VPS to process the changes: 

reboot

 

Optional: extra private IPs 

Do you want to set up more internal IPs? You then add an extra (kind of) sub-adapter for each IP address separately in your configuration:

auto ens7:0
allow-hotplug ens7:0
iface ens7:0 inet static
   address 192.168.1.3
   netmask 255.255.255.0

You use this format per IP address. A third IP address thus gets the interface name ens7:1, a fourth ens7:2 etc.   


Debian 10

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2 

Open your network configuration:

nano /etc/network/interfaces

 

Step 3 

Add the configuration for ens7 at the bottom of the open file. 

auto ens7
iface ens7 inet static
   address 192.168.1.2
   netmask 255.255.255.0 

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 


 

Step 4 

Save your settings and close your editor (ctrl + x > y > enter). Finally, restart your network to process the changes: 

systemctl restart networking

 

Optional: extra private IPs 

Do you want to set up more internal IPs? You then add an extra (kind of) sub-adapter for each IP address separately in your configuration:

auto ens7:0
allow-hotplug ens7:0
iface ens7:0 inet static
   address 192.168.1.3
   netmask 255.255.255.0

You use this format per IP address. A third IP address thus gets the interface name ens7:1, a fourth ens7:2 etc. 


Debian 11

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2 

Open your network configuration:

nano /etc/network/interfaces

 

Step 3 

Add the configuration for ens7 at the bottom of the open file. 

auto ens7
iface ens7 inet static
   address 192.168.1.2
   netmask 255.255.255.0 

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 

Please note: your VPS might use a different interface name (e.g. ens8). This can be checked using the ip a command.


 

Step 4 

Save your settings and close your editor (ctrl + x > y > enter). Finally, restart your VPS to process the changes: 

reboot

 

Optional: extra private IPs 

Do you want to set up more internal IPs? You then add an extra (kind of) sub-adapter for each IP address separately in your configuration:

auto ens7:0
allow-hotplug ens7:0
iface ens7:0 inet static
   address 192.168.1.3
   netmask 255.255.255.0

You use this format per IP address. A third IP address thus gets the interface name ens7:1, a fourth ens7:2 etc. 


FreeBSD

Please note! Although fully based on FreeBSD, the instructions below do NOT work for pfSense. For this, you will always have to add private IPs via the interface of pfSense. 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2 Open the network configuration (Nano is not standard in FreeBSD): 

vi /etc/rc.conf

 

Step 3 

Your private network interface (vtnet1) is probably not yet included in the configuration. Enter the configuration for vtnet1 (the private network interface). Choose an internal IP address that you want to use, for example: 

ifconfig_vtnet1="inet 192.168.1.2 netmask 255.255.255.0"

For example, the result looks like this:

freebsd network configuration with private network


 

Step 4 

Save your settings (:wq!) And run the following command to restart the network: 

/etc/rc.d/netif restart 

You can then test your IP address using a ping command: 

ping 192.168.1.2

Ubuntu 16.04

 

From Ubuntu 16.04, PredictableNetworkInterfaceNames is used and the eth1 interface for the private network interface is no longer used by default. Instead, this interface will be assigned an "ens" interface if you add it to a private network. 

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2 

Open your network configuration: 

nano /etc/network/interfaces

 

Step 3 

Add the configuration for ens7 at the bottom of the open file. 

auto ens7
iface ens7 inet static
  address 192.168.1.2
  netmask 255.255.255.0

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 


 

Step 4 

Save your settings and close your editor (ctrl + x > y > enter). Finally, run the following command to restart the network: 

systemctl restart networking

 

Optional: extra private IPs 

Do you want to set up more internal IPs? You then add an extra (kind of) sub-adapter for each IP address separately in your configuration: 

auto ens7:0
allow-hotplug ens7:0
iface ens7:0 inet static
  address 192.168.1.3
   netmask 255.255.255.0

You use this construction per IP, so a third IP gets the interface name ens7:1, a fourth ens7:2 etc.


Ubuntu 18.04

 

Ubuntu 18.04 has moved away from static interfaces (/etc/network/interfaces) and switched to NetPlan. Netplan is a YAML network configuration abstraction for various backends. Your network configuration now takes place in a yaml file, namely /etc/netplan/01-netcfg.yaml. 

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2

First, check the name of your private network adapter with the command:

ip a

Usually your public interface is called ens3 and the private interface ens7. If yours is called ens4 or ens8 for example, make sure to change the name accordingly in the steps below.



Step 3

Open your network configuration:

nano /etc/netplan/01-netcfg.yaml

 

Step 4

Add the configuration for ens7 at the bottom of the open file. 

ens7:
  dhcp4: no
  addresses:
   - 192.168.1.2/24

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 


 

Step 5

Save your settings and close your editor (ctrl + x > y > enter). Finally, run the following command to restart the network: 

netplan apply

 

Optional: extra private IPs 

Any additional IPs can be added directly under the list of 'addresses' in your configuration as shown in the example below. 

ens7:
  dhcp4: no
  addresses:
   - 192.168.1.2/24
   - 192.168.1.3/24

Ubuntu 20.04

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2

First, check the name of your private network adapter with the command:

ip a

Usually your public interface is called ens3 and the private interface ens7. If yours is called ens4 or ens8 for example, make sure to change the name accordingly in the steps below.


 

Step 3

Open your network configuration:

nano /etc/netplan/01-netcfg.yaml

 

Step 4

Add the configuration for ens7 at the bottom of the open file. Please note that spaces (indentation) must match the existing configuration for your primary network adapter.

ens7:
  dhcp4: no
  addresses:
   - 192.168.1.1/24

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 

In rare instances, the above might not work. If this happens to you, instead use:

ens7:
  dhcp4: no
  addresses: [192.168.1.1/24]

 

Step 5

Save your settings and close your editor (ctrl + x > y > enter). Finally, run the following command to restart the network: 

netplan apply

 

Optional: extra private IPs 

Any additional IPs can be added directly under the list of 'addresses' in your configuration as shown in the example below. 

ens7:
  dhcp4: no
  addresses:
   - 192.168.1.1/24
   - 192.168.1.2/24

Ubuntu 22.04

 

Step 1

Log in to your VPS using SSH or the VPS console.


 

Step 2

First, check the name of your private network adapter with the command:

ip a

Usually your public interface is called ens3 and the private interface ens7. If yours is called ens4 or ens8 for example, make sure to change the name accordingly in the steps below.


 

Step 3

Open your network configuration:

nano /etc/netplan/01-netcfg.yaml

 

Step 4

Add the configuration for ens7 at the bottom of the open file. Please note that spaces (indentation) must match the existing configuration for your primary network adapter.

ens7:
  dhcp4: no
  addresses:
   - 192.168.1.1/24

So, you add a new interface directly below the existing one (ens3). Do not adjust the existing 'public' interface (ens3). 

In rare instances, the above might not work. If this happens to you, instead use:

ens7:
  dhcp4: no
  addresses: [192.168.1.1/24]

 

Step 5

Save your settings and close your editor (ctrl + x > y > enter). Finally, run the following command to restart the network: 

netplan apply

 

Optional: extra private IPs 

Any additional IPs can be added directly under the list of 'addresses' in your configuration as shown in the example below. 

ens7:
  dhcp4: no
  addresses:
   - 192.168.1.1/24
   - 192.168.1.2/24

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0
Matthijs van Beek Admin June 21, 2018 (#1463)

@thunderb1te

Not yet, but this article is on our schedule to receive an overhaul / update (probably late August / early september), in which Ubuntu 18.04 will be included.

0
thunderb1te June 20, 2018 (#1459)

Hebben jullie hier toevallig ook een voorbeeld voor in Ubuntu 18.04?