fail2ban: enable network bans

[casperklein]

Description

Fixes #2669

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (non-breaking change that does improve existing functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (README.md or the documentation under docs/)
• If necessary I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[georglauterbach]

When we update to the latest F2B version in the near future, is this still relevant? I was about to update F2B, and was curious.

[casperklein]

This feature is not implemented upstream yet. There is still an open issue about that.

When the new f2b version came out, I tried it, however lots of f2b tests failed. I fear it's not an drop-in replacement for the current version and might require some adjustments and testing.

[georglauterbach]

This feature is not implemented upstream yet. There is still an open issue about that.

When the new f2b version came out, I tried it, however lots of f2b tests failed. I fear it's not an drop-in replacement for the current version and might require some adjustments and testing.

Understood :)