Cisco IOS XR
| Cisco IOS XR | |
|---|---|
| Developer | Cisco Systems |
| OS family | Unix-like |
| Working state | Current |
| Source model | Closed source |
| Latest release | 25.3.1 / September 16, 2025 |
| Repository |
|
| Supported platforms | NCS 5x0, NCS 5x00, 8000, ASR 9000 and XRv 9000 Series Routers |
| Userland | Linux |
| Official website | Cisco IOS XR |
IOS XR is a release train of Cisco Systems' 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 series of routers.
Architecture
[edit | edit source]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".[1] The microkernel was formerly provided by QNX;[2] versions 6.0 up to 7.5.2 use the Wind River Linux distribution.[3] From version 7.6.1 and onwards, the kernel has been switched to OpenEmbedded.
IOS XR aims to provide the following advantages over the earlier IOS trains:
- Improved high availability (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 software infrastructure and a two-stage forwarding architecture)
- A package based software distribution model (allowing optional features such as multicast routing and MPLS 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 for system management (making use of a generic, XML management interface)
History
[edit | edit source]IOS XR was announced along with the CRS-1 in May 2004.[4] 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 instead of QNX, and was released in September 2013[5]
- 6.1.1 - Introduces support for the 64-bit Linux-based IOS XR operating system on ASR 9000 series [6]
Differences between IOS and IOS XR
[edit | edit source]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.[7]
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
See also
[edit | edit source]References
[edit | edit source]- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ QNX press release Confirming use of their microkernel in IOS XR
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
External links
[edit | edit source]- Cisco Content Hub
- Cisco Feature Navigator
- Cisco IOS XR Support Page
- Cisco Aggregation Services Router 9000 Series Support Page
- Cisco Carrier Routing System Support Page
- Cisco multimedia documentation - covering IOS XR and its supported systems
- Cisco Security Advisories
- HEAnet's New Network and Working with IOS-XR