C H A P T E R
7-1
Hardware Installation Guide for the Cisco 4451-X Integrated Service Routers
OL-27644-01
7
Online Insertion and Removal (OIR) and
Hot-Swapping
Online insertion and removal (OIR) enables you to replace faulty modules without affecting system
operation, which is similar to hot-swapping. OIR commands are issued before removing a module and
after installing a module. When performing OIR, an identical module must be used to replace the original
one. If performing OIR on multiple modules within a router, perform the operation on one module at a
time.
Requirement
The module must be in energywise full-power mode for OIR commands to be issued. If the module is in
energywise power-saving or shutdown mode, OIR commands can not be issued, and the module should
not be removed.
The difference between hot-swapping and OIR is that OIR requires performing Cisco IOS commands
before and after the OIR. Hot-swapping is strictly a hardware function and requires no commands. Not
all router components or modules use OIR, or can be hot swapped.
The following items use OIR in the Cisco ISR 4451-Xs:
•
Service Modules (SMs)
•
Network Interface Modules (NIMs)
•
External CompactFlash memory
•
SFPs
•
USB devices
The following items can be hot swapped:
•
Fan tray
•
Power supply—only when the router is backed up with the optional PSU
