5-5
Type
Description
Major-Fault
The assistant-edge node initiates Major-Fault packets to notify the edge
node of SRPT failure when an SRPT between edge node and
assistant-edge node is torn down.
RRPPDUs of subrings are transmitted as data packets in the primary ring, while RRPPDUs of
the primary ring can only be transmitted within the primary ring.
RRPP Timers
When RRPP checks the link state of an Ethernet ring, the master node sends Hello packets out
the primary port according to the Hello timer and determines whether its secondary port
receives the Hello packets based on the Fail timer.
z
The Hello timer specifies the interval at which the master node sends Hello packets out the
primary port.
z
The Fail timer specifies the maximum delay between the master node sending Hello
packets out the primary port and the secondary port receiving the Hello packets from the
primary port. If the secondary port receives the Hello packets sent by the local master node
before the Fail timer expires, the overall ring is in Health state. Otherwise, the ring transits
into Disconnect state.
In an RRPP domain, a transit node learns the Hello timer value and the Fail timer value on the
master node through the received Hello packets, ensuring that all nodes in the ring network are
consistent in the two timer settings.
How RRPP Works
Polling mechanism
The polling mechanism is used by the master node of an RRPP ring to check the Health state of
the ring network.
The master node sends Hello packets out its primary port periodically, and these Hello packets
travel through each transit node on the ring in turn.
z
If the ring is complete, the secondary port of the master node will receive Hello packets
before the Fail timer expires and the master node will keep the secondary port blocked.
