Switch User Manual

3-72 Sun Fire B1600 Blade System Chassis Switch Administration Guide • June 2003
■ Maximum Age – The maximum time (in seconds) the switch can wait without
receiving a configuration message before attempting to reconfigure. All switch
ports (except for designated ports) receive configuration messages at regular
intervals. Any port that ages out the STA information provided in the last
configuration message it received becomes the designated port for the connected
LAN. If it is a root port, a new root port is selected from among the switch ports
connected to the network. (References to “ports” in this section mean “interfaces,”
which include both ports and trunks.)
Specify a value from the higher of 6 or [2 x (Hello Time + 1)] to the lower of 40 or
[2 x (Forward Delay - 1)]. The default is 20 seconds.
■ Forward Delay – The maximum time (in seconds) the switch waits before
changing states (for example, from discarding to learning to forwarding). This
delay is required because every device must receive information about topology
changes before it starts to forward frames. In addition, each port needs time to
listen for conflicting information that would make it return to a discarding state;
otherwise, temporary data loops might result.
Specify a value from the higher of 4 or [(Max. Message Age / 2) + 1] to 30
seconds. The default is 15 seconds.
The following global parameters are statistical values and cannot be changed:
■ Number of Topology Changes – The number of times the spanning tree has been
reconfigured.
■ Last Topology Change – The time since the spanning tree was last reconfigured.
Web Interface: Configuring Basic STA Settings
1. Open Switch Config ⇒ Spanning Tree ⇒ Basic Configuration.
2. Modify the required parameters.
3. Click Save.