Nortel Networks 2000 Manual De Usuario
53
Using the Business Policy Switch 2000 Version 1.2
Spanning Tree Fast Learning
Spanning Tree Fast Learning is an enhanced port mode supported by the BPS
2000. If you enable Spanning Tree Fast Learning on a port with no other bridges,
the port is brought up more quickly following the switch initialization or a
spanning tree change. The port goes through the normal blocking and learning
states before the forwarding state, but the hold times for these states is the bridge
hello timer (2 seconds by default) instead of the bridge forward delay timer (15
seconds by default). If the port sees a BPDU it will revert to regular behavior.
2000. If you enable Spanning Tree Fast Learning on a port with no other bridges,
the port is brought up more quickly following the switch initialization or a
spanning tree change. The port goes through the normal blocking and learning
states before the forwarding state, but the hold times for these states is the bridge
hello timer (2 seconds by default) instead of the bridge forward delay timer (15
seconds by default). If the port sees a BPDU it will revert to regular behavior.
With BPS 2000 software version 1.1 and higher, the port set with Fast Learning
can forward data immediately, as soon as the switch learns that the port is enabled.
can forward data immediately, as soon as the switch learns that the port is enabled.
Fast Learning is intended for access ports where only one device is connected to
the switch (as in workstations with no other spanning tree devices). It may not be
desirable to wait the usual 30 to 35 seconds for spanning tree initialization and
bridge learning.
the switch (as in workstations with no other spanning tree devices). It may not be
desirable to wait the usual 30 to 35 seconds for spanning tree initialization and
bridge learning.
ASCII configuration file
Beginning with software version 1.2, the BPS 2000 can download a user-editable
ASCII configuration file from a TFTP server. You can load the ASCII
configuration file automatically at boot time or on demand using the management
systems (console menus or CLI). Once downloaded, the configuration file
automatically configures the switch or stack according to the Command Line
Interface (CLI) commands in the file. This feature allows the flexibility of
generating command configuration files that can be use on several switches or
stacks with minor modifications. (The maximum size for an ASCII configuration
file is 100 KBs; larger configuration files must be split into multiple files.)
ASCII configuration file from a TFTP server. You can load the ASCII
configuration file automatically at boot time or on demand using the management
systems (console menus or CLI). Once downloaded, the configuration file
automatically configures the switch or stack according to the Command Line
Interface (CLI) commands in the file. This feature allows the flexibility of
generating command configuration files that can be use on several switches or
stacks with minor modifications. (The maximum size for an ASCII configuration
file is 100 KBs; larger configuration files must be split into multiple files.)
Note:
Use Spanning Tree Fast Learning with caution. This procedure is
contrary to that specified in the IEEE 802.1D standard for Spanning Tree
Protocol (STP), in which a port enters the blocking state following the
initialization of the bridging device or from the disabled state when the port is
enabled through configuration.
Protocol (STP), in which a port enters the blocking state following the
initialization of the bridging device or from the disabled state when the port is
enabled through configuration.