RUGGEDCOM RSG2488
User Guide
Chapter 3
Device Management
Configuring Port Mirroring
67
Parameter
Description
Speed (in Megabit-per-second or Gigabit-per-second). If auto-negotiation is enabled,
this is the speed capability advertised by the auto-negotiation process. If auto-
negotiation is disabled, the port is explicitly forced to this speed mode.
AUTO means advertise all supported speed modes.
Dupx
Synopsis:
{ Auto, Half, Full }
Default:
Auto
Duplex mode. If auto-negotiation is enabled, this is the duplex capability advertised by
the auto-negotiation process. If auto-negotiation is disabled, the port is explicitly forced
to this duplex mode.
AUTO means advertise all supported duplex modes.
LFI
Synopsis:
{ Off, On }
Default:
Off
Enabling Link-Fault-Indication (LFI) inhibits transmitting link integrity signal when the
receive link has failed. This allows the device at far end to detect link failure under all
circumstances.
NOTE
This feature must not be enabled at both ends of a fiber link.
Alarm
Synopsis:
{ On, Off }
Default:
On
Disabling link state alarms will prevent alarms and LinkUp and LinkDown SNMP traps
from being sent for that port.
NOTE
If one end of the link is fixed to a specific speed and duplex type and the peer auto-negotiates,
there is a strong possibility that the link will either fail to raise, or raise with the wrong settings on
the auto-negotiating side. The auto-negotiating peer will fall back to half-duplex operation, even
when the fixed side is full duplex. Full-duplex operation requires that both ends are configured
as such or else severe frame loss will occur during heavy network traffic. At lower traffic volumes
the link may display few, if any, errors. As the traffic volume rises, the fixed negotiation side will
begin to experience dropped packets, while the auto-negotiating side will experience excessive
collisions. Ultimately, as traffic load approaches 100%, the link will become entirely unusable.
These problems can be avoided by always configuring ports to the appropriate fixed values.
4. Click
Apply
.
Section 3.7.7
Configuring Port Mirroring
Port mirroring is a troubleshooting tool that copies, or mirrors, all traffic received or transmitted on a designated
port to specified mirror port. If a protocol analyzer is attached to the target port, the traffic stream of valid frames
on any source port is made available for analysis.
Select a target port that has a higher speed than the source port. Mirroring a 100 Mbps port onto a 10 Mbps port
may result in an improperly mirrored stream.
Frames will be dropped if the full-duplex rate of frames on the source port exceeds the transmission speed of the
target port. Since both transmitted and received frames on the source port are mirrored to the target port, frames
will be discarded if the sum traffic exceeds the target port’s transmission rate. This problem reaches its extreme in
the case where traffic on a 100 Mbps full-duplex port is mirrored onto a 10 Mbps half-duplex port.
