Web Management Guide-R07

Table Of Contents
Chapter 13
| Basic Administration Protocols
LBD Configuration
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If the recover time is not enabled (checkbox unmarked), all ports placed in
shutdown state can be restored to operation using the Release button. To
restore a specific port, re-enable Admin status on the Configure Interface page.
The recover-time is the maximum time when recovery is triggered after a loop
is detected. The actual interval between recovery and detection will be less
than or equal to the recover-time.
Action – Specifies the protective action the switch takes when a loopback
condition is detected. (Options: Block, None, Shutdown; Default: Shutdown)
Block – When the response to a detected loopback condition is set to block
user traffic, and a loopback is detected on a port which a member of a
specific VLAN, packets belonging to that VLAN are dropped at the
offending port. Under these conditions, loopback detection control frames
may be untagged or tagged depending on the ports VLAN membership
type. Ingress filtering for the port is enabled automatically if not already
enabled by other commands. The port’s original setting for ingress filtering
will be restored when loopback detection is disabled.
None - No action is taken.
Shutdown – When the response to a detected loopback condition is set to
shut down a port, and a port receives a control frame sent by itself, this
means that the port is in looped state, and the VLAN in the frame payload is
also in looped state with the wrong VLAN tag. The looped port is therefore
shut down.
When the loopback detection response is changed, any ports placed in
shutdown state by the loopback detection process will be immediately
restored to operation regardless of the remaining recover time.
Trap – Sends a trap when a loopback condition is detected, or when the switch
recovers from a loopback condition. (Options: Both, Detect, None, Recover;
Default: None)
Both – Sends an SNMP trap message when a loopback condition is
detected, or when the switch recovers from a loopback condition.
Detect – Sends an SNMP trap message when a loopback condition is
detected.
None – Does not send an SNMP trap for loopback detection or recovery.
Recover – Sends an SNMP trap message when the switch recovers from a
loopback condition.
Release – Releases all interfaces currently shut down by the loopback
detection feature.