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MRP messages
MRP messages include Join, New, Leave, and LeaveAll. Join and New messages are declarations, and
Leave and LeaveAll messages are withdrawals.
Join message
An MRP participant sends a Join message to request the peer participant to register the specific attribute.
When receiving a Join message from the peer participant, an MRP participant registers the specific
attribute and propagates the Join message to all other participants on the device. After receiving the Join
message, other participants determine whether to send a Join message to their respective peer
participants depending on the attribute status on the local interfaces.
Join messages sent from a local device to a peer device include the following types:
•
JoinEmpty
—Declares an unregistered attribute. For example, an MRP participant joins an existing
static VLAN and sends a Join message before registering the VLAN. The Join message is a
JoinEmpty message. VLANs created manually and locally are called "static VLANs," and VLANs
learned through MRP are called "dynamic VLANs."
•
JoinIn
—Declares a registered attribute. For example, an MRP participant joins an existing static
VLAN and sends a Join message after registering the VLAN, or the MRP participant receives a Join
message propagated by another participant on the device and sends a Join message after
registering the VLAN. The Join message is a JoinIn message.
New message
Similar to a Join message, a New message enables MRP participants to register attributes.
•
When the MSTP topology changes, an MRP participant sends a New message to the peer
participant to declare the topology change.
•
Upon receiving a New message from the peer participant, an MRP participant registers the
attributes in the message and propagates the New message to all other participants on the device.
After receiving the New message, other participants send the New message to their respective peer
participants.
Leave message
MRP sends a Leave message to the peer participant to deregister attributes that an MRP participant has
deregistered.
When the local MRP participant receives a Leave message from the peer participant, it deregisters the
specific attribute and propagates the Leave message to all other participants on the device. After
receiving the Leave message, other participants determine whether to send the Leave message to their
respective peer participants depending on the attribute status on the device. For example, if a Leave
message is received for a dynamic VLAN that is not registered by any participant on the device, the
VLAN is deleted on the device and the Leave message is sent to the peer participants. If a Leave message
for a static VLAN is received, the Leave message will not be sent to the peer participants.
LeaveAll message
Each MRP participant is configured with an individual LeaveAll timer. When the timer expires, the MRP
participant sends LeaveAll messages to the peer participant.
Upon sending or receiving a LeaveAll message, the local participant starts the Leave timer and
determines whether to send a Join message to request the peer participant to re-register the specific
attributes depending on the attribute status on the local participant. MRP re-registers the specific
attributes in the received Join message before the Leave timer expires. When the Leave timer expires,