Protocol Timers - Cisco Nexus 7000 Series Configuration Manual

Rapid PVST+
Figure 7: Proposal and Agreement Handshaking for Rapid Convergence
The switch learns the link type from the port duplex mode; a full-duplex port is considered to have a
point-to-point connection and a half-duplex port is considered to have a shared connection. You can override
the default setting that is controlled by the duplex setting.
This proposal/agreement handshake is initiated only when a nonedge port moves from the blocking to the
forwarding state. The handshaking process then proliferates step-by-step throughout the topology.

Protocol Timers

This table describes the protocol timers that affect the Rapid PVST+ performance.
Table 10: Rapid PVST+ Protocol Timers
Variable
Hello timer
Forward delay timer
Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.x
98
Configuring Rapid PVST+ Using Cisco NX-OS
Description
Determines how often each device broadcasts BPDUs
to other network devices. The default is 2 seconds,
and the range is from 1 to 10.
Determines how long each of the listening and
learning states last before the port begins forwarding.
This timer is generally not used by the protocol, but
it is used when interoperating with the 802.1D
spanning tree. The default is 15 seconds, and the range
is from 4 to 30 seconds.