Could not apply configuration

This topic explains a message that may appear in the Tailscale client and the actions you can take to address it. For a list of currently documented messages in the Tailscale admin console and client, refer to the main Messages topic.

Message displayed in the client

Could not apply configuration

An error occurred applying the Tailscale envknob configuration stored on disk: <error>

Reference ID

apply-disk-config

Why you're seeing this message

A Tailscale envknob is another name for a Tailscale-specific environment variable or parameter used to adjust how the Tailscale client works within the tailnet. These settings start with prefixes, including TS_, PORT, and HTTP_PROXY, and used by the part of Tailscale that runs in the background, called tailscaled, also known as the Tailscale daemon.

Here are some reasons why this message might display:

• An envknob is not properly configured.
• The envknob conflicts with other client settings.
• You do not have permission to run the tailscaled process on the node or device.
• A configuration file on the disk containing envknobs might be corrupted or unreadable.

What to do

Here are some things you can try to resolve this issue:

• Restart your Tailscale client using the client UI, or run the CLI commands tailscale down followed by tailscale up.
• Verify that your envknobs are properly configured and spelled correctly.
• Verify that your envknobs do not conflict with other Tailscale settings such as exit nodes, subnets, or your tailnet policy file.

Additional information

• For information about the tailnet policy file, refer to Tailnet policy file.
• For information about tailscaled, refer to tailscaled daemon.