conntrack
Table of Contents
1. Overview
1.1. Definition
- conntrack is a system used for network connection tracking.
- Integral to many firewall software setups, especially in Linux-based systems.
1.2. Functionality
- Monitors state of active connections.
- Manages connection state information for network protocols such as TCP, UDP.
- Utilizes a state table for tracking connections.
1.3. Importance
- Enhances security by helping to filter and manage network traffic.
- Allows for more complex and dynamic firewall rules.
- Important for network performance tuning and understanding traffic patterns.
1.4. Key Components
- conntrack-tools: a suite of user-space utilities to manage the active connections.
- nfconntrack: a kernel module handling the connection tracking functionality.
1.5. Connection to Firewalls
- Used extensively in iptables/netfilter frameworks.
- Provides stateful inspection capabilities, allowing decisions based on connection states.