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System Tunables Tab¶
The System Tunables tab under System > Advanced provides a means to set run-time FreeBSD system tunables, also known as sysctl OIDs. In almost all cases, we recommend leaving these tunables at their default values. Firewall administrators familiar with FreeBSD, or users doing so under the direction of a developer or support representative, may want to adjust or add values on this page so that they will be set as the system starts.
The tunables on this page are different from Loader Tunables.
Loader Tunables are read-only values once the system has booted, and
those values must be set in
Creating and Editing Tunables¶
To edit an existing tunable, click .
To create a new tunable, click New at the top of the list.
When editing or creating a tunable, the following fields are available:
sysctlOID to set
The value to which the Tunable will be set.
Some values have formatting requirements. Due to the vast number of sysctl OIDs, the GUI does not validate that the given Value will work for the chosen Tunable.
An optional description for reference.
Click Save when the form is complete.
Tunable OIDs and Values¶
There are many OIDs available from
sysctl, some of them can be set, some are
read only outputs, and others must be set before the system boots as Loader
Tunables. The full list of OIDs and their possible values is outside the scope
of this book, but for those interested in digging a little deeper, The sysctl
manual page from FreeBSD contains detailed instructions and information.