User's Manual

Table Of Contents
289
Users Manual of CS-6306R
Figure 9: The edge node blocks the edge port at the interruption of the channel.
3. Channel recovery
When the link of the major ring and the communication between the edge node and the assistant node
resumes, the channel of the sub-ring protocol packet resumes to the normal function. In this case, the master
node of the sub ring receives the Hello packet again, which is transmitted by the master node itself, and
therefore it switches to the Complete status, blocks the secondary port and transmits the
RING-UP-FLUSH-FDB packet to the ring. At the same time, the status of the edge port of the assistant node
changes from Edge-Preforwarding to Forwarding, guaranteeing a smooth communication among all nodes on
the ring. The following figure shows that the channel is resumed and then the communication on the ring is
also resumed.
Before the edge node opens the blocked edge port, the secondary port of the
master node on the sub ring should be blocked to prevent the broadcast storm from
happening.
Figure 10: Channel recovery
Fast Ethernet Ring Protection Configuration 27.2
27.2.1 Requisites before Configuration
Before configuring MEAPS, please read the following items carefully:
One of important functions of the ring protection protocol is to stop the broadcast storm, so please make
sure that before the ring link is reconnected all ring nodes are configured. If the ring network is connected
in the case that the configuration is not finished, the broadcast storm may easily occur.
Set the ring protection protocol to realize the compatibility of STP. The users are allowed to set “no
spanning-tree”, SSTP, RSTP and MSTP.
After an instance of the ring's node is set, users are forbidden to change the basic information of the node
(excluding the time parameters) unless the current ring’s node is deleted and then reset.
If you run show to browse the configured node and find its state is init, it shows that the node’s