Hardware Reference
15
C613-03022-00 REV F
Hot Swapping
Hot Swapping is the installation or removal of a component (such as an NSM)
without powering down or restarting the switch or router.
NSMs can be hot swapped in and out of switches and routers that are running
Software Release 2.3.1 or later.
To find out which software release your switch or router is running, use the
command:
SHOW RELEASE
PICs can be swapped only if they are installed in an AR040 NSM. PICs installed in bays
on base units (e.g., the chassis PIC bays on AR700 Series routers) cannot be hot
swapped.
Hot Swapping the AR040 NSM with PICs
When an AR040 NSM with PIC cards is hot swapped out, and an identical
combination of AR040 and PICs is hot swapped into the same bay, the software
configurations for the PIC interfaces are preserved across the hot swap. In this
case, modules configured to the PIC interfaces transfer to the newly swapped
in interfaces.
When an AR040 NSM with PICs is hot swapped out and a different
combination of AR040 and PICs is hot swapped into the same bay, new
interface instances are created for any new PIC types or PIC types that are in
different bays (the old interface instances are discarded). For any PIC in the
combination that is replaced by a PIC of the same type, interface instances are
preserved.
The recessed Hot Swap button must be used when hot swapping PICs. See the PIC
Quick Install Guide or PIC Hardware Reference for the correct procedure for hot
swapping PICs.
How to Hot Swap an NSM
This procedure requires Software Release 2.3.1 or later.
WARNING: Failure to follow this procedure when hot swapping an NSM will
cause the switch or router to crash, and may damage the switch or router and
files stored in Flash.
The AT-AR040 NSM can be hot swapped with PICs installed in its PIC bays. There is
no need to remove the PICs before hot swapping. See “Behaviour of Hot Swapped
Interfaces” on page 17 for information on the operational characteristics of hot swapped
interfaces.
