METRObility Optical Systems R821-1S, Инструкция по установке и эксплуатации

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Management
Note: Do not send ARP requests (pings) to the R821 during its initial-
ization. All ARP requests received during the probing phase
5
are inter-
preted as address collisions and discarded. If a collision occurs, the
R821 will immediately discard the address it is verifying and generate
another one.
If DHCP is enabled, every five minutes following a successful self-
generated address assignment, the R821 will attempt to acquire its
addressing information by locating a DHCP server.
If DHCP is disabled, the R821 will maintain its last known IP addressing
information regardless of how the information was acquired, even if it
was self-generated using zeroconf.
Copper Line
Quality (CLQ)
Tester
The R821 features a built-in cable tester that uses time domain reflecto-
metry to identify and locate problems along the copper cable on Port 1. If
a fault occurs, you can initiate the CLQ test via software and to see what
type of problem occurred (open circuit, short circuit, or impedance
mismatch). The test also provides the distance to the fault along the
cable from the R821. The distance accuracy is +/- 2 meters.
Far End Fault
Far End Fault (FEF) is only applicable to the fiber port (Port 2). FEF
allows a management station to receive notification of a failure in a
remote R821’s fiber port receiver. When two services line cards are
connected through their fiber ports, FEF allows the local card to detect a
failure in the remote card’s fiber receiver. When FEF is enabled, the local
R821 will send an SNMP alarm to its trap destination(s) if a Far End
Fault condition is detected. No alarm will be sent if the condition occurs
but FEF is disabled.
Flow Control
Full-Duplex Flow Control
Full-duplex flow control is provided to avoid dropping frames during
periods of network congestion. If flow control is enabled, the port will
issue a PAUSE frame whenever there is no buffer space available for
incoming frames. Full-duplex flow control applies only when the port is in
full-duplex mode with auto-negotiation enabled. Additionally, during the
negotiation process, the port’s link partner must indicate support for
PAUSE frames.
5.The probing phase lasts approximately 6 seconds.