Single Fiber Fault Detection - Nortel 8600 Configuration Manual

For more information about configuring CANA, see (Enterprise Device
Manager) "Configuring an Ethernet port" (page
10/100/1000 Mbit/s ports" (page
Mbit/s ports" (page

Single Fiber Fault Detection

Use Single Fiber Fault Detection (SFFD) to detect remote faults on
1 Gigabit Ethernet fiber ports. When a fiber break occurs, data can be lost.
SFFD detects the fault and, to stop packet loss, disables the port.
For SFFD to work properly, both ends of the fiber connection must have
SFFD enabled and autonegotiation disabled. Because the Ethernet
Routing Switch 8600 supports autonegotiation, it is not necessary to
enable SFFD on fiber-based links with an Ethernet Routing Switch 8600
at both ends. In this case, enable autonegotiation (and disable SFFD)
on both switches. When you enable SFFD on the Ethernet Routing
Switch 8600, SFFD detects single fiber faults and brings down faulty links
immediately. If the port is part of a multilink trunk, traffic fails over to other
links in the MLT group. After you correct the fault, SFFD starts the link
within 12 seconds.
SFFD is supported on the following Ethernet Routing Switch 8600
modules:
•
8630GBR
•
8648GBRS and fiber-optic gigabit ports of 8634XGRS
•
8648GTR
Because Nortel recommends that you use RFI through autonegotiation
whenever it is supported by both link devices, SFFD is disabled by default.
You can configure SFFD through the CLI and NNCLI.
To make sure that SFFD works properly, adhere to the following rules:
•
When both ends of a fiber link support autonegotiation, use the default
setting (disabled) for SFFD.
•
Configure both ends of a fiber connection with the same setting. If you
configure a port at one end of a fiber link for SFFD, then you must
configure the port at the other end for SFFD.
•
Enable only one option on each port—either SFFD or
autonegotiation—not both. If you enable SFFD on a port, you
must disable autonegotiation. If you enable autonegotiation for a port,
you must disable SFFD.
•
Configure all ports in a multilink trunk with the same option. If you
enable SFFD on one port in a multilink trunk, you must enable SFFD
on all ports in the multilink trunk and disable autonegotiation. If you
NN46205-503 04.01 21 December 2009
Copyright © 2008-2009 Nortel Networks. All Rights Reserved.
37), or (NNCLI)
52).
Nortel Ethernet Routing Switch 8600
Configuration — Ethernet Modules
Ethernet module concepts 17
24), (CLI) "Configuring
"Configuring 10/100/1000