How to Configure a Private Network on Fedora

Introduction

When deploying a Vultr cloud server with a private network, you need to manually configure the private adapter. The examples shown in this guide are IPv4, but Vultr supports both IPv4 and IPv6. Vultr also supports multiple VLANs over a single private network interface with 802.1q tags. You'll find your server's information on the information page under Settings > IPv4. In the example below, the public network address is 192.0.2.123, and the private network address is 10.10.10.3. You'll find configuration samples for your server by clicking "View our networking configuration tips and examples."

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Private Networking Notes

• When you enable private networking, you may use any RFC1918 private address as long as there are no conflicts with your other instances. Valid addresses include:
  • 10.0.0.0/8
  • 172.16.0.0/12
  • 192.168.0.0/16
• Private IP addresses in the customer portal are suggestions. You are not required to use the suggested private IP addresses.
• You can attach a maximum of 126 instances to a single private network. If you require more, please contact our engineering team.
• Private networks can not communicate between locations, regardless of IP addressing. For example, server instances in Miami can not see private networks in Dallas.
• Private networks do not have DHCP, and you must manually manage your IP address space or install a DHCP server on your private network.
• For optimal performance, set the private network adapter MTU to 1450 when configuring the NIC at the OS level.
• We also have guides to configure multiple private networks.

Fedora 24 through 28

Verify that private networking is enabled for your cloud server. Your private network device is ens7. Your public network device is ens3.

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

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

Populate the file with the following configuration. Replace 10.10.10.3 with your IP address.

DEVICE=ens7
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=static
IPADDR=10.10.10.3
NETMASK=255.255.0.0
NOZEROCONF=yes
IPV6INIT=no
MTU=1450

Restart the connection, or reboot.

# systemctl restart network.service

Fedora 29 through 32

Verify that private networking is enabled for your cloud server. Your private network device is ens7. Your public network device is ens3.

Run the following commands. Replace 10.10.10.3 with your IP address.

# nmcli con add con-name private-net ifname ens7 type ethernet ipv4.method 'manual' ipv4.addresses '10.10.10.3/24' 802-3-ethernet.mtu 1450
# nmcli con up private-net

Optional: Use systemd-networkd

If you prefer to use systemd-networkd configuration instead of the default Fedora configuration, follow these steps. These instructions apply to Fedora 29 through 32.

1. Edit the public.network configuration.

   # nano /etc/systemd/network/public.network
   

   Add the following text.

   [Match]
   Name=ens3
   
   [Network]
   DHCP=yes
   

2. Save and exit the file.

3. Edit the private.network configuration.

   # nano /etc/systemd/network/private.network
   

   Add the following text. Replace 10.10.10.3 with your IP address.

   [Match]
   Name=ens7
   
   [Link]
   MTUBytes=1450
   
   [Network]
   Address=10.10.10.3/20
   

4. Save and exit the file.

5. Enable the resolver and make a symlink:

   # systemctl enable systemd-resolved
   # systemctl start systemd-resolved
   # rm -f /etc/resolv.conf
   # ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf
   

6. Enable and start the new network services.

   # systemctl enable systemd-networkd
   # systemctl start systemd-networkd
   

7. Disable NetworkManager and the network scripts.

   # systemctl disable NetworkManager
   # systemctl disable network
   

If the network fails to load, use the Vultr Web Console to make corrections. You may need to reboot in rare cases.

Manage Private Networks via API

The Vultr API offers several endpoints to manage private networks.