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CrossFire 8600/860 5 Token-Ring Switches v. 1. 2, P/N: 710001641 Switch Configuratio n
IEEE 802.1D Spanning Tree Protocol (STP)When the IEEE 802.1D Spanning Tree Protocol is active, a port within tha t domain
will require several seconds to make the transition from the blocking state to the
forwarding state, when the port is initially activated (e .g. joins an existing ring or
activates a dedicated link.) Some client or server applications may attempt to
establish session activity during this time, res ulting in error messages indicating a
connection failure. These applications should be configured to wait at least 30
seconds after the LAN link is active, before att empting to establis h session act ivity.
This delay can be reduced by modifying the 802.1D Spanning Tree Protocol defaul t
parameters.
If STP is enabled on a dedicated port, and a stati on is at tac he d to it, it take s at le ast
30 seconds for the port to transition Down → Listening → Learning →
Forwarding .
The IPX client and server stations may have given up before then. And the first
many PINGs get lost.
In general, STP should not be enabled on ports, which are intended for dedic ated
stations. Shared media do not have the same problem, because the port wil l stay
attached to the Hub, even though all stations have closed.
Another reason for not enabling STP on dedicated ports is, that the whole network
will go into Topology Change state each time a station opens o r closes. This will
cause the whole network to use short aging timers, so all address tables will be
trashed. The result is a lot of unknown station broadcasts, before the tables
converge again.
To disable STP on a port, select the STP Mode Forwarding for this port. Refer to
the “STP Mode” parameter on page104.