FRR

FRR
Name	FRR
Author	GNU Zebra (origin), FRRouting community
Developer	FRRouting Project, Open Source contributors
Released	2016
Operating system	Linux, BSD
License	GNU GPL v2

FRR FRR is an open-source routing suite that implements IPv4 and IPv6 control-plane protocols for routers and network appliances. It provides production-grade implementations of routing protocols used by operators, vendors, and academic projects, enabling interoperability with systems such as Cisco Systems, Juniper Networks, Arista Networks, Nokia (company), and Cumulus Networks. FRR integrates with software and platforms including Linux, FreeBSD, OpenBSD, Debian, Red Hat Enterprise Linux, and orchestration systems like Ansible, Kubernetes, and OpenStack.

Overview

FRR implements a modular set of routing daemons that together provide functionality comparable to proprietary suites used by Cisco Systems and Juniper Networks. The project emerged from forks and community-driven efforts around projects such as Quagga and GNU Zebra, and has attracted contributors from companies including Google, Facebook, Microsoft, Broadcom, and NTT. FRR is commonly deployed in data centers, service provider networks, and virtualized network functions alongside platforms like Linux Containers (LXC), Docker, and Kubernetes. The suite focuses on protocol correctness, interoperability with standards bodies like the IETF, and integration with control frameworks such as Open Network Operating System and SONiC.

Architecture and Components

FRR uses a multi-daemon architecture where each protocol runs as a separate daemon communicating via an internal message bus and APIs. Core daemons include implementations of protocols historically important to internet routing: routing information protocols derived from work initially in GNU Zebra and Quagga, with specific daemons for protocols such as Open Shortest Path First, Border Gateway Protocol, Routing Information Protocol, and Intermediate System to Intermediate System. The suite provides a central configuration and management daemon that interacts with a unified routing table and a forwarding plane provided by platforms like the Linux kernel routing stack, Netlink, and hardware forwarding ASICs from vendors including Broadcom and Mellanox Technologies. Auxiliary components include a route manager, a Zebra daemon for kernel-programming interactions, and high-availability features compatible with solutions used by Amazon Web Services and Google Cloud Platform.

Routing Protocol Support

FRR contains mature implementations of widely deployed protocols. Notable protocol support includes implementations compatible with specifications from the IETF: Border Gateway Protocol (BGP) including BGP-LS and EVPN extensions, Open Shortest Path First (OSPFv2/OSPFv3), Intermediate System to Intermediate System (IS-IS), Routing Information Protocol (RIP and RIPng), Bidirectional Forwarding Detection (BFD), and multicast mechanisms used in conjunction with standards like PIM-SM. FRR also supports protocol extensions and features used in modern networks such as segment routing interoperability with vendors like Cisco Systems and traffic engineering constructs standardized in IETF documents. Operators integrate FRR with route reflectors, route servers at internet exchange points like LINX and DE-CIX, and peering configurations common to networks operated by Level 3 Communications and regional carriers.

Configuration and Management

FRR provides a command-line interface patterned after industry de facto standards used by Cisco IOS and Juniper Junos, enabling network engineers familiar with those platforms to adopt FRR in environments managed by automation tools such as Ansible, SaltStack, Puppet, and Chef. Configuration files follow a syntax compatible with traditional network OS conventions, and FRR exports management interfaces via vtysh, JSON over Unix sockets, and streaming telemetry options suited for ingestion by collectors like Prometheus and Grafana. Integration adapters exist for orchestration and intent systems including Kubernetes CNI plugins, OpenStack Neutron, and controller platforms such as ONOS and OpenDaylight.

Performance and Scalability

FRR is designed to scale in environments ranging from small edge routers to large-scale route servers and internet-scale deployments. Performance depends on factors like kernel route installation mechanisms (e.g., Netlink), hardware offload capabilities of ASICs from vendors such as Broadcom and NXP Semiconductors, and tuning parameters familiar to operators from platforms like Linux and FreeBSD. FRR supports granular control of route processing, route-reflector topologies, and route-policy constructs that large operators such as Google and Facebook leverage for prefix filtering, route aggregation, and scaling BGP tables in the presence of full internet routing tables. Benchmarks and community reports compare FRR against other control-plane implementations used by cloud providers like Amazon Web Services.

Security and Hardening

FRR implements security features and best practices aligned with operational requirements set by organizations such as IETF working groups and regional internet registries like ARIN and RIPE NCC. Security measures include TCP MD5 and TCP-AO for BGP sessions, TLS-based transport for management connections, and role-based access commonly enforced in deployments integrated with identity systems like LDAP and RADIUS. Hardening recommendations mirror those from operators at Internet2 and large CSPs: strict prefix-lists, prefix-origin validation using RPKI, route filtering, control-plane policing, and secure configuration management via automation frameworks including Ansible and HashiCorp Vault.

History and Development

FRR originated from community forks and consolidations of earlier projects such as Quagga and GNU Zebra. Since its formation, the FRRouting Project has attracted corporate sponsorship and contributors from companies including Cumulus Networks, Cisco Systems, Facebook, Google, and Microsoft. Development follows open-source governance and collaboration norms familiar from projects hosted by foundations and repositories used by GitHub and other code-hosting platforms. The project lifecycle includes feature contributions driven by production needs from data center operators, standards alignment via IETF participation, and continual integration testing against vendor platforms like Arista Networks and Juniper Networks.

Category:Routing software