3Com 5500-SI Configuration Manual page 61

Table 44 Configure loopback detection for Ethernet port (continued)
Operation
Enter the Ethernet port view
Enable the loopback detection
function for a specified port
Enable the loopback detection
and control function for Trunk
ports and Hybrid ports
Configure the system to
detect loopback in all the
VLANs with Trunk ports and
Hybrid ports
Display the loopback detection
information
Loopback detection function for a port is enabled only when the loopback-detection
enable command is enabled under both system view and port view.
When the undo loopback-detection enable command is used under system view, the
loopback detection function will be disabled for all ports.
Setting Loopback Detection for an Ethernet Port
Use the following command to enable port loopback detection and set the detection
interval for the external loopback condition of each port. If there is a loopback port
found, the Switch will put it under control.
Other correlative configurations function only when port loopback detection is
enabled in System View.
Perform the following configuration in the view listed in Table 45.
Table 45 Setting Loopback Detection for the Ethernet Port
Operation
Enable loopback detection on the port (System
View/Ethernet Port View)
Disable loopback detection on the port (System
View/Ethernet Port View)
Enable the loopback controlled function of the
trunk and hybrid ports (Ethernet Port View)
Disable the loopback controlled function of the
trunk and hybrid ports (Ethernet Port View)
Set the external loopback detection interval of
the port (System View)
Restore the default external loopback detection
interval of the port (System View)
Configure that the system performs loopback
detection to all VLANs on Trunk and Hybrid
ports (Ethernet Port View)
Configure that the system only performs
loopback detection to the default VLANs on the
port (Ethernet Port View)
Ethernet Port Configuration Introduction
Command Description
interface -
interface-type
interface-number
loopback-detection Optional.By default, the loopback
enable detection function is disabled.
loopback-detection Optional.By default, the loopback
control enable detection and control function is disabled.
loopback-detection Optional.
per-vlan enable By default, system only detects loopback
for the default VLANs with Trunk ports
and Hybrid ports.
display Optional.
loopback-detection This command can be used under any
view
Command
loopback-detection enable
undo loopback-detection enable
loopback-detection control
enable
undo loopback-detection control
enable
loopback-detection
interval-time time
undo loopback-detection
interval-time
loopback-detection per-vlan
enable
undo loopback-detection
per-vlan enable
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