D-Link DGS-3620-52T CLI Guide - Page 420

xStack® DGS-3620 Series Layer 3 Managed Stackable Gigabit Switch CLI Reference Guide 31-5 config erps raps_vlan Description This command is used to set the R-APS VLAN parameters. The ring_mel command is used to configure the ring MEL for an R-APS VLAN. The ring MEL is one field in the R-APS PDU. Note that if CFM (Connectivity Fault Management) and ERPS are used at the same time, R-APS PDU is one of a suite of Ethernet OAM PDU. The behavior for forwarding of R-APS PDU should follow the Ethernet OAM. If the ring MEL is not higher than the highest MEL of the MEPs on the ring ports, the R-APS PDU cannot be forwarded on the ring. The ring_port command is used to configure the port that participates in the ERPS ring. Restrictions apply for ports that are included in a link aggregation group. A link aggregation group can be configured as a ring port by specifying the master port of the link aggregation port. Only the master port can be specified as a ring port. If the specified link aggregation group is eliminated, the master port retains its ring port status. The rpl command is used to configure the RPL port and the RPL owner. RPL port - Specifies one of the R-APS VLAN ring ports as the RPL port. To remove an RPL port from an R-APS VLAN, use the none designation for rpl_port. RPL owner - Specifies the node as the RPL owner. The protected_vlan command is used to configure the VLANs that are protected by the ERPS function. The R-APS VLAN cannot be the protected VLAN. The protected VLAN can be one that has already been created, or it can be used for a VLAN that has not yet been created. The timer commands are used to configure the protocol timers: Holdoff timer - Hold-off timer is used to filter out intermittent link faults when link failure occurs. This timer is used during the protection switching process when link failure occurs. When a ring node detects a link's failure, it will start the hold off timer. It will report the link failure event (R-APS BPDU with SF flag) after the link failure is confirmed within this period of time. Guard timer - Guard timer is used to prevent ring nodes from receiving outdated R-APS messages. This timer is used during the protection switching process when link failure recovers. When the link node detects that the link failure is recovered, it will report the link failure recovery event (R-APS PDU with NR flag) and start the guard timer before the guard timer expires, all received R-APS messages are ignored by this ring node. Therefore, the blocking state of the recovered link will not be recovered within this period of time. This time should be greater than the maximum expected forwarding delay for which one R-APS message circles around the ring. WTR timer - WTR timer is used to prevent frequent operation of the protection switch due to an intermittent defect. This timer is used during the protection switching process when a link failure recovers. This timer is only used by the RPL owner. When the RPL owner in protection state receives R-APS PDU with an NR flag, it will start the WTR timer. The RPL owner will block the original unblocked RPL port and start to send R-APS PDU with an RB flag after the link recovery is confirmed within this period of time. 415