IOS XR is a release train of

Cisco Systems Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational digital communications technology conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, ...

' widely deployed Internetwork Operating System (IOS), used on their high-end Network Convergence System (NCS) and carrier-grade routers such as the ASR 9000 series and

Carrier Routing System Carrier Routing System (CRS) is a modular and distributed core router developed by Cisco Systems Inc that enables service providers to deliver data, voice, and video services over a scalable IP Next-Generation Network (NGN) infrastructure. In a ne ...

series of routers.

Architecture

According to Cisco's product literature, IOS XR shares very little infrastructure with the other IOS trains, and is instead built upon a " preemptive, memory protected, multitasking, microkernel-based

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

". The microkernel was formerly provided by QNX; versions 6.0 onwards use the

Wind River Linux Wind River Systems, also known as Wind River (trademarked as Wndrvr), is an Alameda, California–based company, subsidiary of Aptiv PLC. The company develops embedded system and cloud software consisting of real-time operating systems software, ...

distribution. IOS XR aims to provide the following advantages over the earlier IOS trains: * Improved

high availability High availability (HA) is a characteristic of a system which aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period. Modernization has resulted in an increased reliance on these systems. F ...

(largely through support for hardware redundancy and fault containment methods such as protected memory spaces for individual processes and process restartability) * Better scalability for large hardware configurations (through a

distributed Distribution may refer to: Mathematics *Distribution (mathematics), generalized functions used to formulate solutions of partial differential equations *Probability distribution, the probability of a particular value or value range of a varia ...

software infrastructure and a two-stage forwarding architecture) * A package based software distribution model (allowing optional features such as

multicast routing Multicast routing is one of the routing protocols in IP networking. CISCO Security Research & Operations- 3 June 201Understanding Unicast Reverse Path Forwarding , Cisco -unicast-reverse-path-forwarding/ref> There are several multicast rou ...

and

MPLS Multiprotocol Label Switching (MPLS) is a routing technique in telecommunications networks that directs data from one node to the next based on labels rather than network addresses. Whereas network addresses identify endpoints the labels identif ...

to be installed and removed while the router is in service) * The ability to install package upgrades and patches (potentially while the router remains in service) * A web-based

GUI The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, inste ...

for system management (making use of a generic,

XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. T ...

management interface)

History

IOS XR was announced along with the CRS-1 in May 2004. The first generally available version was 2.0. Some significant releases include the following. * 3.2 – first generally available version for the 12000 router series * 3.9 – first generally available version for the ASR 9000 router series * 5.0 – first generally available version for the NCS6000 series, which is based upon a

Linux kernel The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally authored in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU ...

instead of QNX, and was released in September 2013 * 6.1.1 - Introduces support for the 64-bit Linux-based IOS XR operating system on ASR 9000 series

Differences between IOS and IOS XR

An example BGP configuration for IOS and IOS XR is shown. More examples can be found in the Cisco document ''Converting Cisco IOS Configurations to Cisco IOS XR Configurations''.{{cite web, title=Converting Cisco IOS Configurations to Cisco IOS XR Configurations, url=http://www.cisco.com/c/en/us/td/docs/ios_xr_sw/iosxr_r3-2/conversion/reference/guide/cnvt32/cn32main.pdf, website=cisco.com, publisher=Cisco Systems, accessdate=August 4, 2017 IOS router bgp 109 no synchronization bgp log-neighbor-changes neighbor 203.0.113.1 remote-as 109 neighbor 203.0.113.1 update-source Loopback0 no auto-summary IOS XR router bgp 109 neighbor 203.0.113.1 remote-as 109 update-source Loopback0

References

External links

Cisco Content HubCisco Feature Navigator
- covering IOS XR and its supported systems
Cisco Security AdvisoriesHEAnet's New Network and Working with IOS-XR
Cisco products

Architecture

History

Differences between IOS and IOS XR

See also

References

External links