preforwarding-time
The default preforwarding time interval is 300 milliseconds.
MRP configuration mode
The preforwarding time interval must be at least twice the value of the hello time or a multiple of the hello time.
When MRP is enabled, all ports begin in the preforwarding state.
An interface changes from the preforwarding state to the forwarding state when the port preforwarding time expires. This occurs if the port does not receive a Ring Health Packet (RHP) from the master, or if the forwarding bit in the RHPs received by the port is off (indicating a break in the ring). The port heals the ring by changing its state to forwarding. If a member port in the preforwarding state does not receive an RHP within the preforwarding time, the port assumes that a topology change has occurred and changes to the forwarding state.
The secondary port on the master node changes to the blocking state if it receives an RHP, but changes to the forwarding state if the port does not receive an RHP before the preforwarding time expires. A member node preforwarding interface also changes from preforwarding to forwarding if it receives an RHP whose forwarding bit is on.
If Unidirectional Link Detection (UDLD) is also enabled on the device, RUCKUS recommends that you set the MRP preforwarding time slightly higher than the default of 300 ms; for example, to 400 or 500 ms.
The
no form of the command sets the preforwarding time interval to the default.