UFW stands for Uncomplicated Firewall, and is a program for managing a netfilter firewall. It provides a command line interface and aims to be uncomplicated and easy to use.
UFW can be found in the testing repository. Read Alpine_Linux_package_management#Repository_pinning to enable the testing repository.
Once the testing repository has been enabled, UFW can be installed by issuing the following command:
The following is a simple configuration that will deny all incoming and outgoing data communication by default and allow incoming SSH, outgoing DNS and NTP traffic:
The following lines are only needed the first time you install the package:
Check the status of UFW: