When the Smoothwall is restarted the SFP in our network card does not turn on

Article #: Product Castle
KB-144 All All Releases


When the Smoothwall device is restarted, SFP on the network cards does not turn on, requiring manually disconnecting and reconnecting the SFP from the server.


Smoothwall has an upper limit on interfaces configured of 20. This includes physical interfaces, and virtual interfaces i.e. VLANs, Bonds, etc. If this limit is exceeded it will cause problems upon booting.


The solution requires editing files on command line to remove legacy settings to free up some interface slots. This can be done in the following way:

Firstly, connect to the Smoothwall via SSH using a program such as PuTTY, on port 222. Then run the command:

cd /settings/ethernet/nics

Once you have done that, if you then list the contents of this folder (using the command “ls”) you should see the following

The next step will be to check the contents of all of these files, and remove any that are invalid or not in use. You can do this using the command “cat settings-X” where X is the number of each file.

This will show you the configuration of each file, make note of the number of any that are empty, or any that contain invalid configuration.

To remove the settings from the configuration, firstly run the following command:

Vim /settings/ethernet/ifacemap.json

You will see a file that looks something like the following:

The number referencing which “settings” file this interface is contained within. Any lines mapped to a settings file that was either not configured, or configured incorrectly will need to be deleted. This can be done by moving the cursor to the line in questions, and pressing the “d” key twice. Please make sure not to delete the brackets {}

To exit the editor and commit the changes, press the Escape key, followed by :wq (colon, “w” key, “q” key)

Finally, to finish this change, in the UI browse to Network > Configuration > Interfaces, and edit any setting and click save (no changes are necessary)


Last updated: Author: Contributions by:
03 August 2017 Harley Greenwood