ALM-3276800214 A loop is detected on the Layer 2 network connected to the interface

Description

LBDT/4/PORTTRAP: OID [OID] Loopback exists on interface([INTEGER1]) [OCTET1] ([OCTET2]), loopback detection status: [INTEGER2], auto loop detection for trap only on VLAN [OCTET3].(Status 1:normal; 2:block; 3:shutdown; 4:trap; 5:nolearn; 6:quitvlan)

A loop is detected on the Layer 2 network connected to the interface.

Attribute

Alarm ID	Alarm Severity	Alarm Type
3276800214	Warning	Communication alarm

Parameters

Name	Meaning
OID	Indicates the MIB object ID of the alarm.
INTEGER1	Indicates the interface index.
OCTET1	Indicates the interface name.
OCTET2	An alarm is reported when a loop is detected in a VLAN (not a VLAN in which loops are detected automatically and only alarms are reported). If untagged packets are used to detect the loop, the value of this parameter is Untagged. If tagged packets are used to detect the loop, the value of this parameter is the VLAN ID in the VLAN tag.
INTEGER2	Indicates the loop detection status on the interface.
OCTET3	Indicates the list of VLANs where loops are detected automatically. Only alarms are reported.

Impact on the System

After the interface is shut down, all traffic on the interface is interrupted.

After the interface is blocked, all traffic except protocol packets is interrupted.

After nolearn is configured on the interface, the interface does not learn MAC addresses.

After the trap function is configured on the interface, the interface continuously reports traps.

After the quitvlan function is configured on the interface, the interface is deleted from the VLAN where a loop occurs and services of traffic in the VLAN are interrupted.