Network Helper

What is Network Helper?

Network Helper is a host-side service which automatically sets a static IPv4 address and gateway for your Linode. This means you do not need to manually reconfigure your Linode’s network addressing when you:

• Deploy a Linode
• Add a public or private IPv4 address
• Restore from a backup
• Migrate your Linode to a new data center
• Clone from another Linode

Network Helper is enabled by default, and works by detecting which distribution is booting and then modifying the appropriate network configuration files. If Network Helper is unable to determine the operating system during boot, or if you boot an unsupported operating system, Network Helper will not attempt to write any new configuration files. Be aware that Network Helper configures only IPv4 addressing; your Linode’s IPv6 address is assigned by SLAAC.

Caution

If you instead choose to manually configure your Linode’s network interface settings, be the IPv4 or IPv6, you must disable Network Helper for that Linode or your configuration will overwritten during the next boot.

Network Helper Settings

Network Helper can be enabled or disabled globally for your account, or on a per-Linode basis. Network Helper can still be toggled on and off for specific Linodes, regardless of whether enabled or disabled globally.

Global

When Network Helper is enabled globally, all new Linodes created on your account will have Network Helper enabled by default.

1. Click on Account in the sidebar of the Linode Cloud Manager.

2. Click on the Settings tab. Set the switch under the Network Helper section to the desired setting; blue is enabled, gray is disabled.

3. Click the Save button.

Single (Per-Linode)

1. Click on Linodes link in the sidebar of the Linode Cloud Manager.

2. Select the Linode you would like to enable Network Helper for.

3. Click on the Configurations tab. Then, click on the Edit option next to the configuration profile the Linode is currently using.

4. A side-panel menu will appear with the configuration profile’s settings. Under the Filesystem/Boot Helpers section, toggle the Auto-configure networking switch to the desired setting; blue is enabled, gray is disabled.

5. Click the Submit button.

What Files are Modified

The specific files Network Helper modifies varies by distribution.

Note

Network Helper is not supported on the CoreOS distribution

Alpine

Network Helper configures /etc/network/interfaces.

Arch & Ubuntu (18.04 LTS and later)

Network Helper configures /etc/systemd/network/05-eth0.network.

CentOS & Fedora

Network Helper configures /etc/sysconfig/network-scripts/ifcfg-eth0.

Debian & Ubuntu (versions before 18.04 LTS)

Network helper configures /etc/network/interfaces and /etc/resolv.conf.

Gentoo

Network Helper configures /etc/conf.d/net and /etc/resolv.conf.

OpenSUSE

Network Helper configures /etc/sysconfig/network/ifcfg-eth0, /etc/sysconfig/network/routes, and /etc/resolv.conf.

Slackware

Network Helper configures /etc/rc.d/rc.inet1.conf and /etc/resolv.conf.

What is Modified in Those Files

Below are example network configuration files for a Debian 9 Linode with Network Helper enabled:

File: /etc/network/interfaces

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# Generated by Linode Network Helper # Wed Jan 9 21:30:02 2019 UTC # # This file is automatically generated on each boot with your Linode's # current network configuration. If you need to modify this file, please # first disable the 'Auto-configure Networking' setting within your Linode's # configuration profile: # - https://manager.linode.com/linodes/config/lin1?id=13561415 # # For more information on Network Helper: # - https://www.linode.com/docs/platform/network-helper # # A backup of the previous config is at /etc/network/.interfaces.linode-last # A backup of the original config is at /etc/network/.interfaces.linode-orig # # /etc/network/interfaces auto lo iface lo inet loopback auto eth0 allow-hotplug eth0 iface eth0 inet6 auto iface eth0 inet static address 203.0.113.5/24 gateway 203.0.113.1

File: /etc/resolv.conf

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# Generated by Linode Network Helper # Wed Jan 9 21:30:02 2019 UTC # # This file is automatically generated on each boot with your Linode's # current network configuration. If you need to modify this file, please # first disable the 'Auto-configure Networking' setting within your Linode's # configuration profile: # - https://manager.linode.com/linodes/config/lin1?id=13561415 # # For more information on Network Helper: # - https://www.linode.com/docs/platform/network-helper # # A backup of the previous config is at /etc/.resolv.conf.linode-last # A backup of the original config is at /etc/.resolv.conf.linode-orig # domain members.linode.com search members.linode.com nameserver 66.228.53.5 nameserver 96.126.122.5 nameserver 96.126.124.5 nameserver 96.126.127.5 nameserver 198.58.107.5 nameserver 198.58.111.5 nameserver 23.239.24.5 nameserver 173.255.199.5 nameserver 72.14.179.5 nameserver 72.14.188.5

In addition to the network interface file (again, specific to this Debian example), Network Helper will create:

• A copy of the interface and resolver file as the distribution provided it: .interfaces.linode-orig and /etc/.resolv.conf.linode-orig. Note that Network Helper does not modify /etc/resolv.conf on all of our distributions.

• A copy of the interface and resolver files from the previous boot: .interfaces.linode-last and /etc/.resolv.conf.linode-last. If you manually changed either of these file before the previous boot, you’ll find them saved there.

Use the following command to restore manual changes made before the previous reboot. Be sure to replace /etc/network/interfaces with the network interface file for your distribution from above.

mv /etc/network/.interfaces.linode-last /etc/network/interfaces