Nortel Passport 15000 Hardware Description page 281

— both gigabit Ethernet ports are connected to the same LAN or subnet
• for no card sparing between VSP3s, connect the VSP3
Note: Configure both Ethernet ports for sparing at the same time. If you
configure only one of the two Ethernet ports on a VSP3 card, and you
wish to add the second one later, then configure the second port for
sparing and physically connect it. The newly added port becomes the
standby. The only method to trigger a manual switchover between two
spared gigabit Ethernet ports is to delete the configuration of the active
port, thereby forcing a switchover to the standby. Traffic is lost during the
switchover. To provide a standby for the newly active port, then configure
the formerly active port again. It automatically becomes the standby.
A switchover from the active to the standby VSP3 card occurs provided:
• the attribute switchoverOnFailure under the component IpInterface is
enabled (for the description of components, refer to 241-5701-060
Passport 7400, 15000, 20000 Components)
• the PVG application is without an active port for the continuous period
specified by the attribute switchoverHoldoffTime under the component
IpInterface
• at least one of the gigabit Ethernet ports has been active since the VSP3
card started up after a reboot or a switchover (which also stops the VSP3
from constantly resetting or switching over when the ports are
disconnected or have failed)
• the standby card is in service at the time a switchover is attempted
Cable the sparing connections between each VSP3 and the far-end according
to the capabilities of the far-end equipment. For an example of cable
connections, refer to the figure "Example of spared VSP3 cards in a LAN
hardware configuration" (page 282).
After powering up both ends of the VSP3 connection, the Ethernet port that
comes up first automatically becomes the active port, and the second one (if
configured for sparing) becomes the standby.
Once both ports are in service, the switchover occurs automatically when the
far-end detects a loss of signal from the active Ethernet port.
Chapter 4 Control and function processors 281
Passport 15000, 20000 Hardware Description 5.2S2