- Landscape documentation: https://landscape.canonical.com/static/doc/user-guide/
- Fail2ban manual: https://www.fail2ban.org/wiki/index.php/MANUAL_0_8
- sshd_config file guide: https://www.ssh.com/ssh/sshd_config/
- Ubuntu CVE tracker: https://people.canonical.com/~ubuntu-security/cve/
- Password haystacks (find out how secure your password is): https://www.grc.com/haystack.htm
- Krebs on security (a great security blog): https://krebsonsecurity.com/
- SECURITY NOW (a very informative security podcast): https://twit.tv/shows/security-now
- ShieldsUP! (a useful tool to see which ports your router has open): https://www.grc.com/shieldsup
Further reading
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