Linux Firewall Adoption Rates 2026 (Iptables Vs Nftables Vs Firewalld)

firewalld and UFW were active on 88.4% of home and small-business Linux installations in 2025, according to SQ Magazine — yet the firewall engine running underneath those tools has shifted dramatically. nftables entered the Linux kernel in January 2014 and has since displaced iptables as the default backend on every major Linux distribution released after 2019. This article documents where iptables, nftables, and firewalld stand in 2026: which tools run by default, which still dominate legacy infrastructure, and what the data shows about migration patterns.

Linux Firewall Adoption Rates: iptables vs nftables vs firewalld in 2026

The Linux firewall picture in 2026 is a three-layer story. At the kernel level, nftables is now the standard Netfilter subsystem on modern distributions. At the management layer, firewalld (on Red Hat-family systems) and UFW (on Debian/Ubuntu systems) handle configuration for the majority of deployments. iptables, which was the standard for nearly two decades, now runs primarily through a compatibility shim called iptables-nft or persists on older systems that have not been upgraded.

The Netfilter Project officially placed iptables in legacy maintenance mode, directing all new deployments to nftables. On Ubuntu 22.04 and later, when you run an iptables command, the system routes it through the nftables backend automatically via iptables-nft unless an administrator has explicitly switched to iptables-legacy. This means iptables syntax is still in wide use, but the underlying engine handling those rules is increasingly nftables.

Which Linux Distributions Default to nftables?

The shift to nftables at the distribution level has been steady since 2019. Debian 10 (Buster) was among the first major distributions to adopt nftables as the default packet filtering backend. Ubuntu followed in October 2020 with the 20.10 (Groovy Gorilla) release, making the nftables backend the default for the iptables, ip6tables, arptables, and ebtables tools system-wide. Red Hat Enterprise Linux 8 (released May 2019) ships firewalld with nftables as the backend. Fedora 32 removed the downstream patch that had previously defaulted firewalld to iptables, aligning Fedora with the upstream firewalld project’s nftables default.

Source: Debian Wiki, Ubuntu Security Documentation, Red Hat Documentation, Fedora Project Wiki

nftables vs iptables: Market Presence by Distribution Share

Because firewall tool adoption follows distribution defaults, distribution market share data provides a reasonable proxy for nftables penetration. Red Hat Enterprise Linux leads enterprise servers with 43.1% market share in 2025. RHEL 8 and later default to firewalld over nftables, meaning a substantial portion of enterprise Linux servers run nftables as the effective firewall engine even when administrators interact with firewalld commands. Ubuntu accounts for 33.9% of enterprise deployments and over 60% of public cloud Linux instances, with its nftables backend default having been in place since late 2020.

Source: Command Linux — Linux Distribution Market Share Statistics 2025; Canonical

iptables vs nftables Backend: Estimated Active Usage Split

No single authoritative survey tracks the iptables-vs-nftables split across all Linux servers worldwide. However, combining distribution market share with their default backend configurations produces an estimate of where the installed base sits. Systems still running RHEL 7, CentOS 7, Ubuntu 18.04 LTS, or equivalent enterprise distributions use iptables either directly or as the firewalld backend. Enterprises that have not migrated to a post-2019 distribution remain the largest source of active iptables deployments in 2026.

Source: Netfilter Project; Red Hat Documentation; Debian Wiki; Ubuntu Security Documentation — estimated based on distribution default configurations

Linux Firewall Adoption Rates in Enterprise Environments

Enterprise adoption of Linux servers continues to grow — Linux captured 44.8% of the server operating system market in 2024. Within that installed base, firewall tool usage reflects the distribution split. RHEL 8 and 9 deployments run firewalld with nftables. Organizations that standardized on RHEL 7 or CentOS 7, which reached end of life in June 2024, face pressure to migrate, and migration to RHEL 8 or 9 means adopting the nftables backend by default.

The Linux security patch cadence is a related driver. As enterprise security teams respond to rising CVE counts — 3,529 Linux kernel CVEs were recorded in 2024 — organizations maintaining RHEL 7 systems past end-of-life face compounding risk. Migration to supported distributions inherently moves those deployments to nftables-backed firewall stacks.

Source: Red Hat Product Life Cycles; Canonical Ubuntu Release Schedule; Debian Wiki

firewalld Usage Statistics and Its Role in the Transition

firewalld occupies a distinct position in this picture: it is a management frontend, not a firewall engine. It translates zone-based policy commands into nftables rules on RHEL 8+ and Fedora 32+, or into iptables rules on older systems. The enterprise Linux installed base is heavily RHEL-centric — 72.6% of Fortune 500 companies run mission-critical workloads on Linux as of 2025, and RHEL leads that market with 43.1% share. That makes firewalld the dominant management interface for a large share of enterprise Linux firewall configurations, even as nftables handles the actual packet processing underneath it.

Firewalld upstream adopted nftables as the default backend before either RHEL or Fedora made the switch in their distributions. The Fedora Project Wiki notes that firewalld upstream had already been shipping nftables as the default for two minor releases before Fedora 32 aligned with that change in 2020. This upstream-first adoption pattern means firewalld users on current distributions are running nftables whether they know it or not.

Source: Fedora Project Wiki; Red Hat Documentation; Ubuntu Security Documentation; Debian Wiki

Linux Firewall Adoption in Cloud and Container Environments

Cloud and container workloads represent an area where nftables adoption has accelerated independently of distribution defaults. Kubernetes production deployment reached 80% in 2024, up from 66% in 2023, and Linux powers 78% of all Kubernetes clusters globally. SafeIT Experts noted massive nftables adoption in Kubernetes and cloud-native environments in 2025 specifically. This reflects both the distribution shift and active engineering work to support nftables in container networking tools.

Docker historically injected its own iptables rules, which created compatibility friction when firewalld switched to the nftables backend. The Fedora Project’s change documentation from the Fedora 32 cycle explicitly listed this Docker-firewalld interaction as a known issue requiring resolution. By 2025, the ecosystem had largely adapted — both Docker and Kubernetes tooling had updated their Netfilter integration to handle nftables backends.

Source: Command Linux — Linux Container & Kubernetes Adoption Statistics; SafeIT Experts Firewall Effectiveness Comparison 2025

iptables in Legacy and Ongoing Deployments

Despite the distribution-level shift to nftables, iptables remains in active use across a significant portion of the Linux server fleet. Systems that have not been upgraded from RHEL 7, CentOS 7, Ubuntu 18.04 LTS, or older Debian releases continue running iptables. Additionally, many long-running servers carry firewall configurations that were written as iptables scripts — these frequently remain in place even after an OS upgrade, particularly when the administrator uses the iptables-nft compatibility layer that accepts iptables syntax while routing rules to the nftables kernel engine.

The iptables-translate tool, which converts iptables rules to nftables syntax, has helped reduce migration friction. Still, industry commentary from TuxCare, Zenarmor, and linuxmind.dev consistently notes that iptables “remains prevalent” and that administrators should expect to encounter iptables-protected systems for years ahead. The Netfilter Project’s maintenance-mode designation does not mean iptables stops functioning — it means new feature development has moved to nftables while iptables receives only security and stability fixes.

Source: Red Hat Product Life Cycles; Canonical; Fedora Project Wiki; Netfilter Project

Linux Firewall Security: nftables vs iptables CVE Comparison

Security posture is one factor driving migration from iptables to nftables. SafeIT Experts’ October 2025 firewall effectiveness analysis found no major CVE against nftables at the time of review, while other firewall solutions carried active CVEs requiring urgent patching. The cleaner architecture of nftables — a virtual machine that executes compiled bytecode rather than iptables’ protocol-specific code duplicated across IPv4, IPv6, ARP, and Ethernet bridging — reduces the attack surface from code duplication. The Linux malware and vulnerability data for 2026 reinforces the importance of keeping firewall stacks on maintained codebases: brute-force attacks represent 89% of endpoint behaviors on Linux systems, making properly configured firewalls a critical first line of defense.

The Linux encryption adoption statistics tell a parallel story — administrators applying security hardening in one area (encryption) increasingly pair it with updated firewall infrastructure. Organizations that have migrated to RHEL 8+, Ubuntu 20.04+, or Debian 10+ gain nftables as a side effect of staying on supported distributions, without requiring a separate firewall migration decision.

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