TrueNAS SCALETrueNAS SCALE Nightly Development Documentation
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Advanced Settings

Advanced Settings provides configuration options for the console, syslog, kernel, sysctl, replication, cron jobs, init/shutdown scripts, system dataset pool, isolated GPU device(s), self-encrypting drives, system access sessions, allowed IP addresses, audit logging, and global two-factor authentication.

Advanced settings have reasonable defaults in place. A warning message displays for some settings advising of the dangers of making changes. Changing advanced settings can be dangerous when done incorrectly. Use caution before saving changes.

Make sure you are comfortable with ZFS, Linux, and system configuration, backup, and restoration before making any changes.

SCALE Advanced Settings Screen
Figure 1: SCALE Advanced Settings Screen

This article provides information on sysctl, system dataset pool, setting the maximum number of simultaneous replication tasks the system can perform, and managing sessions.

Managing Allowed IP Addresses

Use the System Settings > Advanced screen Allowed IP Addresses configuration screen to restrict access to the TrueNAS SCALE web UI and API.

Entering an IP address limits access to the system to only the address(es) entered here. To allow unrestricted access to all IP addresses, leave this list empty.

Managing Sysctl Variables

Use Add on the Sysctl widget to add a tunable that configures a kernel module parameter at runtime.


The Add Sysctl or Edit Sysctl configuration screens display the settings.


Enter the sysctl variable name in Variable. Sysctl tunables configure kernel module parameters while the system runs and generally take effect immediately.

Enter a sysctl value for the loader in Value.

Enter a description and then select Enabled. To disable but not delete the variable, clear the Enabled checkbox.

Click Save.

Managing the System Dataset Pool

Storage widget displays the pool configured as the system dataset pool and allows users to select the storage pool they want to hold the system dataset. The system dataset stores core files for debugging and keys for encrypted pools. It also stores Samba4 metadata, such as the user and group cache and share-level permissions.


Configure opens the Storage Settings configuration screen.

Storage Settings Configuration Screen

If the system has one pool, TrueNAS configures that pool as the system dataset pool. If your system has more than one pool, you can set the system dataset pool using the Select Pool dropdown. Users can move the system dataset to an unencrypted pool, or an encrypted pool without passphrases.


Users can move the system dataset to a key-encrypted pool, but cannot change the pool encryption type afterward. If the encrypted pool already has a passphrase set, you cannot move the system dataset to that pool.

Swap Size lets users enter an amount (in GiB) of hard disk space to use as a substitute for RAM when the system fully utilizes the actual RAM.

By default, the system creates all data disks with the specified swap amount. Changing the value does not affect the amount of swap on existing disks, only disks added after the change. Swap size does not affect log or cache devices.

Setting the Number of Replication Tasks

The Replication widget displays the number of replication tasks that can execute simultaneously configured on the system. It allows users to adjust the maximum number of replication tasks the system can execute simultaneously.


Click Configure to open the Replication configuration screen.


Enter a number for the maximum number of simultaneous replication tasks you want to allow the system to process and click Save.

Managing Access (Websocket Sessions)

The Access widget displays a list of all active sessions, including the user who initiated the session and what time it started. It also displays the Token Lifetime setting for your current session. It allows administrators to manage other active sessions and to configure the token lifetime for their account.

The Terminate Other Sessions button ends all sessions except for the one you are currently using. You can also end individual sessions by clicking the logout button next to that session. You must check a confirmation box before the system allows you to end sessions.

The logout icon is inactive for the currently logged in administrator session and active for any other current sessions. It cannot be used to terminate the currently logged in active administrator session.

Token Lifetime displays the configured token duration for the current session (default five minutes). TrueNAS SCALE logs out user sessions that are inactive for longer than that configured token setting for the user. New activity resets the token counter.

If the configured token lifetime is exceeded, TrueNAS SCALE displays a Logout dialog with the exceeded ticket lifetime value and the time that the session is scheduled to terminate.

Click Extend Session to reset the token counter. If the button is not clicked, the TrueNAS SCALE terminates the session automatically and returns to the log in screen.

Click Configure to open the Token Settings screen and configure Token Lifetime for the current account.

Select a value that fits user needs and security requirements. Enter the value in seconds.

The default lifetime setting is 300 seconds, or five minutes.

The minimum value allowed is 30 seconds.

The maximum is 2147482 seconds, or 20 hours, 31 minutes, and 22 seconds.

Click Save.


  • Managing Cron Jobs: Provides information on adding or modifying cron jobs in TrueNAS SCALE.

    • Managing the Console Setup Menu: Provides information on the Console setup menu configuration settings including the serial port, port speed, password protection, and the banner users see.

      • Managing System Logging: Provides information on setting up or changing the syslog server, the level of logging and the information included in the logs, and using TLS as the transport protocol.

        • Managing Init/Shutdown Scripts: Provides information on adding or modifying init/shutdown scripts in TrueNAS SCALE.

          • Managing SEDs: Provides information on adding or modifying self-encrypting drive (SED) user and global passwords in TrueNAS SCALE.

            • Isolating GPU for VMs: Provides information on isolating Graphics Processing Units (GPU) installed in your system.

              • Managing Global 2FA (Two-Factor Authentication): Provides information on SCALE global two-factor authentication, setting it up, and logging in with it enabled.

                • Developer Mode (Unsupported): Provides information on the unsupported SCALE developer mode and how to enable it.