16-11
Spanning Tree Protocol (STP)
How STP Operates
Spanning Tree Protocol
(STP)
If you encounter end nodes that repeatedly indicate server a ccess failure when
attempting to bring up their network connect ion, and you have enabled STP
on the switch, try changing the configuration of the switch ports associated
with those end nodes to STP Fast Mode.
Caution The Fast Mode configuration should be used only on switch ports connected
to end nodes. Changing the Mode to Fast on ports connected to hubs, switches,
or routers may cause loops in your network that STP may not be able to
immediately detect, in all cases. This will cause temporary loops in your
network. After the fast start-up sequence, though, the switch ports operate
according to the STP standard, and will adjust their state to eliminate continu-
ing network loops.
To Enable or Disable Fast Mode for a Switch Port:
You can use either the CLI or the menu interface to toggle between STP Fast
mode and STP Normal mode. (To use the menu interface, see “Menu: Config-
uring STP” on page 16-4.)
Syntax: spanning-tree <port list> mode <fast | norm>
For example, to configure Fast mode for ports C1-C3 and C5:
HP4108(config)# spanning-tree c1-c3,c5 mode fast