Ethernet line cards
are installed in the half-height slots at the rear of the chassis. This design
allows for two half-height line cards to be installed behind every application
card (vertical redundancy). With two line cards installed, booting their
associated application card causes the card in the upper-rear chassis slot to
automatically be made active while the card in the lower-rear chassis slot will
automatically be placed in standby mode. In the event that the active card
experiences a failure, the system will automatically switch traffic to the
standby card in the lower slot.
The XGLC is a
full-height card that supports 1:1 side-by-side redundancy. Side-by-side
(horizontal) redundancy allows two XGLC cards installed in neighboring slots to
act as a redundant pair. Side-by-side pair slots for the XGLC are: 17-18,
19-20, 21-22, 23-26, 27-28, 29-30, and 31-32. If the XGLCs are not configured
for side-by-side redundancy, they run independently without redundancy.
When configured for
side-by-side redundancy, The XGLC is referenced only by the upper slot number
(17 through 23, 26 through 33); the lower slot number is not recognized. All
other configuration commands work as if the side-by-side slots were top-bottom
slots. Configuration commands directed at the bottom slots either fail with
errors or are disallowed.
In the event that a
SPIO experiences a failure, the system will automatically switch traffic to the
redundant SPIO installed behind the redundant SMC.
In the event that an
issue arises that is not severe enough for the system to perform an automatic
switchover, a manual switchover can be performed. Follow the instructions below
to manually initiate a line card or SPIO switchover. These instructions assume
you are at the root prompt for the Exec mode:.