User's Manual

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the ring network is not effective. Then the master node removes the blocking of data VLANs on the secondary
port, ages the local MAC address table, and transmits the RING-DOWN-FLUSH-FDB packets to notify other
nodes.
If the master node receives the HEALTH packets at the secondary port that is open to data VLANs, the ring
network is resumed. In this case, the master node immediately blocks data VLANs on the secondary port,
updates the local topology information and reports other nodes to age the MAC address table through RING-
UP-FLUSH-FDB packets.
You can configure related commands on the Hello-time node and the Fail-time node to
modify the interval for the primary port to transmit the HEALTH packets and the time limit for
the secondary port to wait for the HEALTH packets.
41.4.2 Notification of Invalid Link of Transit Node
After the transit port of the transit node is not effective, the LINK-DOWN packet will be immediately transmitted
by the other transit port to notify other nodes. In normal case, the packet passes through other transit nodes
and finally arrives at one port of the master node.
After the master node receives the LINK-DOWN packet, it thinks that the ring network is invalid. In this case,
the master node removes the blocking of data VLANs on its secondary port, ages the local MAC address table,
transmits the RING-DOWN-FLUSH-FDB packet and notifies other nodes.
41.4.3 Resuming the Link of the Transit Node
After the transit port is resumed, it does not immediately transmit the packets of data VLANs, but enters the
Pre-Forwarding state. A transit port in the pre-forwarding state only transmits and receives the control packets
from the control VLAN.
If there is only one transit port invalid in the ring network and when the port enters the pre-forwarding state,
the secondary port of the master node can receive the HEALTH packet from the primary port again. In this
case, the master node blocks data VLANs on the secondary port again and transmits the notification of ageing
address table outside. After the node with a transit port in pre-forwarding state receives the notification of aging
address table, the node will first modify the pre-forwarding port to the forwarding port and then ages the local
MAC address table.
If a transit mode does not receive the notification of aging address table from the master node, it thinks that
the link to the master node is already out of effect. The transit node will automatically set the pre-forwarding
port to be a forwarding one.
You can configure the related commands through the pre-forward-time node to modify the time for the transit
port to keep the pre-forwarding state.
41.5 Fast Ethernet Ring Protection Configuration
41.6 Default EAPS Settings
Note:
The fast Ethernet protection protocol cannot be set together with STP.