Chapter 3
Device Management
RUGGEDCOM ROS
User Guide
74
Configuring Port Rate Limiting
Parameter
Description
When the port is half-duplex it is accomplished using
'backpressure' where the switch simulates collisions causing the
sending device to retry transmissions according to the Ethernet
backoff algorithm.
When the port is full-duplex it is accomplished using PAUSE
frames which causes the sending device to stop transmitting for a
certain period of time.
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 3.6.7
Configuring Port Rate Limiting
To configure port rate limiting, do the following:
1. Navigate to
Ethernet Ports
»
Configure Port Rate Limiting
. The
Port Rate Limiting
table appears.
