This article explains how to rate limit using the recent module in IPTables.
This article explains how to secure SSH on a linux server.
This article explains how to create comments in IPTable rules.
This article explains how to block HTTP requests using IPTables Firewall for Linux.
This article explains how to create Default Blocks in IPTable rules.
This article provides 8 steps to creating a secure Linux server.
This article explains how to block DNS requests using IPTables Firewall for Linux.