IOS XR Software

Cisco Jan 19, 2025

IOS - Original
- Monolithic operating system - everything in a single bin file
- All processes run in shared memory
- Runs directly on the hardware
IOS-XE - Designed for ASR1000, similar to IOS but on Linux
- Shares much of the base code with IOS
- Uses a distributed architecture
- IOSd instance on top of a Linux kernel
IOS-XR - Complete rewrite, multiprocess, multi-CPU, High availability
- Incudes features important for a service provider
- Command structure significantly different from IOS
- Comes in two versions
  - 32-bit - Runs on top of the QNX Neutrino microkernel
  - 64-bit - Runs on a Linux kernel

IOS/IOS XE applies configurations as soon as it is entered, not persistent until its saved.

IOS-XR uses a two-stage commit system

IOS-XR core and add-on modules (PIE)

Packages are copied to the router and activated
Packages (including the base) can be upgraded individually

show install active shows software packages

show hw-module FPD shows firmware

Major Release . Minor Release . Maintenance Release

Installed from Admin mode

copy tftp disk1/:ASR9K.MCAST.PIE.4.0.1
Install Add
Install Activate
Install Commit / install rollback

Turboboot

Install IOS-XR from ROMMOM

Requires a vm file (bootable)

Default gateway is required

Rommon1>IP_Address=192.168.1.2
Rommon2>IP_SUBNET_MASK=255.255.255.0
Rommon3>TFTP_SERVER=192.168.1.10
Rommon4>DEFAULT_GATEWAY=192.168.1.1
Rommon5>unset BOOT
Rommon6>TURBOBOOT=on,disk0,format
Rommon7>sync
Rommon8>boot tftp://192.168.1.10/ios/hfr-mini-px.vm-4.0.0