Firewalld and IPtables are both tools used for managing firewall rules on Linux systems, but they differ in their design, functionality, and usage. Let’s make a look at a breakdown of the differences and whether they can work together.
IPtables
– What it is: iptables is a traditional and powerful command-line tool for configuring packet filtering rules in the Linux kernel’s Netfilter framework.
– Features:
– Directly manipulates firewall rules.
– Offers granular control over packet filtering, NAT, and port forwarding.
– Rules are static unless manually updated.
– Usage: Typically used by system administrators for precise, low-level firewall configuration.
– Limitations:
– Rules are not persistent across reboots unless explicitly saved (e.g., with iptables-save).
– Complex configurations can be difficult to manage.
firewalld
– What it is: firewalld is a dynamic firewall management tool designed to simplify firewall configuration.
– Features:
– Uses zones and services to define rules in a more abstract way.
– Supports runtime and permanent configurations.
– Dynamic updates without restarting the firewall service.
– Built on top of iptables (or nftables in modern versions).
– Usage: Easier to manage for users who prefer a higher-level, more user-friendly interface.
– Limitations:
– Less granular control compared to iptables.
– May not be suitable for highly customized setups.
| Feature | firewalld | iptables |
| Ease of Use | Easier, abstracted configuration | More complex, manual rules |
| Dynamic Updates | Yes (applies changes immediately) | No (requires manual reload) |
| Persistence | Built-in | Requires manual saving |
| Granularity | Less granular | Highly granular |
| Backend | Uses iptables or nftables | Directly manipulates iptables |
Can They Work Together?
Yes, but caution is required:
– firewalld uses iptables (or nftables) under the hood to implement its rules. When you use firewalld, it automatically generates and manages iptables rules.
– If you manually edit iptables rules while using firewalld, it can lead to conflicts or unexpected behavior because firewalld may overwrite your custom rules during dynamic updates.
– If you want to use both, it’s better to configure firewall rules entirely through firewalld and avoid manually editing iptables rules.
Which Should You Use?
– Use firewalld if you want a simpler, more user-friendly firewall management tool.
– Use iptables if you need fine-grained control over firewall rules or if you’re working on a system where firewalld is not available.
– Modern systems (e.g., RHEL/CentOS 8+, Fedora) are moving toward nftables, which replaces iptables as the backend for both firewalld and direct configuration.
While firewalld and iptables can technically coexist, it’s generally recommended to stick to one tool to avoid conflicts. If you’re looking for simplicity and dynamic management, use firewalld. If you need advanced, low-level control, use iptables directly.