User's Manual

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Users Manual of CS-6306R
27.2.3.6 Browsing the State of the Ring Protection Protocol
Run the following command to browse the state of the ring protection protocol:
Command Purpose
show mether-ring
Browses the summary information about the
ring protection protocol and the ports of ring.
show mether-ring id1 domain id2
Browses the summary information about the
designated ring protection protocol and the
ports of ring.
id1: instance ID of a node
id2: instance ID of a domain (omitted when
it is 0)
show mether-ring id1 domain id2 detail
Browses the detailed information about the
designated ring protection protocol and the
port of Ethernet ring.
show mether-ring id1 domain id2 interface
intf-name
Browses the states of the designated ring
ports or those of the designated common
ports.
Appendix 27.3
27.3.1 Working Procedure of MEAPS
MEAPS adopts three protection mechanisms to support the single-ring or evel-2 multi-ring structure. The
following sections shows, from the complete state to the link-down state, then to recovery and finally to the
complete state again, the details of MEAPS running and the change of the MEAPS topology by typical
examples.
27.3.2 Complete state
The complete state of the ring, which is advocated for only one ring, is monitored and maintained by the
polling mechanism. In complete status, all links on the whole ring are in UP state, which finds expression in
the state of the master node. In order to prevent the broadcast storm from occurring, the master node will
block its secondary port. At the same time, the master node will periodically transmit the Hello packets from its
primary port. These hello packets will pass through the transit node in sequence and finally return to the
master node from its secondary port. The ring in complete state is shown in the following figure. The major
ring and two sub rings are all in complete state. The hello packet of the major ring is only broadcast in the
major ring, while the hello packet of the sub ring can be transparently transmitted through the major ring, then
return to the sub ring, and finally get the secondary port of the master node on the sub ring.