Web Management Guide-R07

Table Of Contents
Chapter 13
| Basic Administration Protocols
LBD Configuration
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LBD Configuration
The switch can be configured to detect general loopback conditions caused by
hardware problems or faulty protocol settings. When loopback detection (LBD) is
enabled, a control frame is transmitted on the participating ports, and the switch
monitors inbound traffic to see if the frame is looped back.
Usage Guidelines
The default settings for the control frame transmit interval and recover time
may be adjusted to improve performance for your specific environment. The
shutdown mode may also need to be changed once you determine what kind
of packets are being looped back.
When loopback detection provided by the commands described in this section
and loopback detection provided by the spanning tree protocol are both
enabled on an interface at the same time, only one function will take effect
depending on whether a spanning tree BPDU or loopback detection control
frame is received first.
When a loopback event is detected on an interface or when a interface is
released from a shutdown state caused by a loopback event, a trap message is
sent and the event recorded in the system log.
Loopback detection must be enabled both globally and on an interface for
loopback detection to take effect.
Configuring Global
Settings for LBD
Use the Administration > LBD (Configure Global) page to enable loopback
detection globally, specify the interval at which to transmit control frames, the
interval to wait before releasing an interface from shutdown state, the response to
a detected loopback, and the traps to send.
Parameters
These parameters are displayed:
Global Status – Enables loopback detection globally on the switch.
(Default: Enabled)
Transmit Interval – Specifies the interval at which to transmit loopback
detection control frames. (Range: 1-32767 seconds; Default: 10 seconds)
Recover Time – Specifies the interval to wait before the switch automatically
releases an interface from shutdown state. (Range: 60-1,000,000 seconds;
Default: 60 seconds)
When the loopback detection mode is changed (enabled or disabled), any
ports placed in shutdown state by the loopback detection process will be
immediately restored to operation regardless of the remaining recover time.