Get a Quote     (408) 943-4100   TrueNAS Discord VendOp_Icon_15x15px Enterprise Support
TrueNAS.com Software Systems Company Community Security iX Portal Download
TrueNAS Enterprise TrueNAS SCALE TrueNAS CORE Compare Editions TrueCommand Software Status FreeNAS
Compare Systems F-Series M-Series H-Series R-Series Mini Series
About iXsystems Our Clients Reviews Careers Awards iX Blog & News iX Website Contact Us
Community Forum Discord TrueNAS GitHub TrueNAS Merch Store
Use Cases Analytics Backup and Archival Cloud Data Mobility File Sharing iX Storj Media Creation Surveillance Virtualization
Industry Automotive Education Gaming Government Healthcare MSP Manufacturing Research & AI Media & Entertainment
Download TrueNAS SCALE Download TrueNAS CORE Get TrueNAS Enterprise Compare TrueNAS Editions Contact an Enterprise Specialist
  1. Documentation Hub
  2. /
  3. TrueNAS SCALE
  4. /
  5. SCALE Tutorials
  6. /
  7. Network
  8. /
  9. Interface Configurations
Edit page
TrueNAS SCALETrueNAS Nightly Development Documentation
This content follows experimental nightly development software. Pre-release software is intended for testing purposes only.
Use the Product and Version selectors above to view content specific to a stable software release.

Interface Configurations

  7 minute read.

TrueNAS SCALE supports configuring different network interface types as part of the various backup, sharing, and virtualization features in TrueNAS. The tutorials in this section guide you through each type of configuration.

Use the Network screen access interface and other network settings. This article covers adding new or changing existing network interfaces, and configuring static and alias IPv4 addresses. For information on configuring IPv6 addresses, see Configuring IPv6.

Why should I use different interface types?

Use LAGG (Link Aggregation) to optimize multi-user performance, balance network traffic, or have network failover protection.

For example, failover LAGG prevents a network outage by dynamically reassigning traffic to another interface when one physical link (a cable or NIC) fails.

Use a network bridge to enable communication between two networks and provide a way for them to work as a single network.

For example, bridges can serve IPs to multiple VMs on one interface, which allows your VMs to be on the same network as the host.

Prepare the system for interface changes by stopping apps, VM NIC devices, and services that can cause conflicts.

  1. Stop running apps before proceeding with network interface changes.
  2. Power off any running virtual machines (VMs) before making interface IP changes.
  3. Remove active NIC devices for VMs.

If you encounter issues with testing network changes, you might need to stop sharing services such as SMB, using the current IP address.

One Static IP Address or Multiple Aliases?

One or More Aliases?

Static IP addresses set a fixed address for an interface that external devices or websites need to access or remember, such as for VPN access.

Use aliases to add multiple internal IP addresses, representing containers or applications hosted in a VM, to an existing network interface without having to define a separate network interface.

In the UI, you can add aliases when adding or editing an existing interface using the Add button to the right of the Aliases. To add a static IP. Click Add again to add an additional alias.

From the Console Setup menu, select option 1 to configure network settings and add alias IP addresses.

Adding an Interface

You can use DHCP to provide the IP address for only one network interface. The DHCP IP address is most likely for your primary network interface configured during installation.

To add another network interface, click Add on the Interfaces widget to display the Add Interface panel. Leave the DHCP checkbox clear. Click Add to the right of Aliases, near the bottom of the Add Interface screen, and enter a static IP address for the interface.

You must specify the type of interface you want to create. Select the interface type from the Type dropdown options: Bridge, Link Aggregation or LAGG, and VLAN or virtual LAN. You cannot edit the interface type after you click Save.

Each interface type displays new fields on the Add Interface panel. Links with more information on adding these specific types of interfaces are at the bottom of this article.

Testing Network Interface Changes

After adding a new interface or changing an existing interface that can impact access to the UI, SCALE displays a Test Changes dialog. This function is intended to prevent changes that can break access to the UI.

Test Network Changes
Figure 1: Test Network Changes

Click Test Changes. You have 60 seconds to test the change. Keep the browser session open, and open a new browser window. Enter the IP address in the URL field and press Enter. The SCALE login screen should display. Enter the administrator login credentials to access the system.

Go to Network in the new browser session and click Save Changes.

If you cannot access the UI, return to the original browser session and click Revert Changes on the Network screen.

Check your configuration, make the necessary changes, and then repeat the test to validate access to the UI. If the change allows access to the UI but is not what you want, click Revert Changes in either the new or original browser session. If the 60 seconds elapses and you do not click Save Changes, the system discards the changes made.

Editing an Interface

To change an existing interface, click on the existing interface in the Interfaces widget and then click on the Edit icon to open the Edit Interface screen.

The Edit Interface and Add Interface settings are identical except for Type and Name which are not editable after adding and saving an interface.

Name shows on the Edit Interface screen, but you cannot change the name. Type only shows on the Add Interface screen. You cannot edit these settings after saving the interface. If you made a mistake with either field and clicked Save, the only option to change either setting is to delete the interface and create a new one with the desired name and type.

If you want to change from a DHCP-provided IP address to a static IP, you must also add the new default gateway and DNS nameservers that work with the new IP address. See Setting Up a Static IP for more information.

After making the changes, click Save.

Test the change as described in Testing Network Interface Changes.

If you delete the primary network interface you can lose your TrueNAS connection and the ability to communicate with the TrueNAS through the web interface!

If you save the changes you lose access to the UI, you might need command line knowledge or physical access to the TrueNAS system to fix misconfigured network settings.

Deleting an Interface

Click the icon for the interface. A delete interface confirmation dialog opens.

Do not delete the primary network interface!

If you delete the primary network interface you lose your TrueNAS connection and the ability to communicate with the TrueNAS through the web interface! You might need command line knowledge or physical access to the TrueNAS system to fix misconfigured network settings.

Adding Alias IP Addresses

Multiple interfaces connected to a single TrueNAS system cannot be members of the same subnet.

You can combine multiple interfaces with link aggregation (LAGG) or a network bridge. Alternatively, you can assign multiple static IP addresses to a single interface by configuring aliases.

Click for more information

When multiple network interface cards (NICs) connect to the same subnet, users might incorrectly assume that the interfaces automatically load balance. However, ethernet network topology allows only one interface to communicate at a time. Additionally, both interfaces must handle broadcast messages since they are listening on the same network. This configuration adds complexity and significantly reduces network throughput.

If you require multiple NICs on a single network for performance optimization, you can use a link aggregation (LAGG) configured with Link Aggregation Control Protocol (LACP). A single LAGG interface with multiple NICs appears as a single connection to the network.

While LACP is beneficial for larger deployments with many active clients, it might not be practical for smaller setups. It provides additional bandwidth or redundancy for critical networking situations. However LACP has limitations as it does not load balance packets.

On the other hand, if you need multiple IP addresses on a single subnet, you can configure one or more static IP aliases for a single NIC.

In summary, we recommend using LACP if you need multiple interfaces on a network. If you need multiple IP addresses, define aliases. Deviation from these practices might result in unexpected behavior.

For a detailed explanation of ethernet networking concepts and best practices for networking multiple NICs, refer to this discussion from National Instruments.

To configure alias IPs to provide access to internal portions of the network, go to the Network screen:

  1. Click on the Edit icon for the interface to open the Edit Interface screen for the selected interface.

  2. Clear the DHCP checkbox to show Aliases. Click Add for each alias you want to add to this interface.

  3. Enter the IP address and CIDR values for the alias(es).

  4. Select DHCP to control the primary IP for the interface.

  5. Click Save.

  6. Click Test Changes when prompted.

Contents