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You can also use the NET 18K dialog box in the HP OpenView application. This dialog can display all the hardware modules. Note that the
For information on how to upgrade your stacker link modules or ATM uplinks that currently do not support 18 KB frames, please contact your dealer or your local representative.
Note: It is most important that you consider the impact of the frame length limit, and make sure that the workstations and servers in the network have been configured to use a maximum frame length of equal or less than the switch. If this is not done you may experience problems after the switch has been installed in the network.
IEEE 802.1D Spanning Tree
When the IEEE 802.1D Spanning Tree Protocol is active, a port within that spanning tree domain will require several seconds to make the transition from the blocking state to the forwarding state, from the time the port is initially activated (for example, joins an existing ring or activates a dedicated link).
Some client or server applications may attempt to establish session activity during this time, resulting in error messages indicating a connection failure. These applications should be configured to wait at least thirty seconds after the LAN link has become active, before attempting to establish session activity. Modifying the 802.1D spanning tree default parameters can reduce this delay. If STP is enabled on a dedicated port (FDX) and a station is attached, it takes at least 30 seconds for the port to do the transition DWN→ LSN→ LRN→ FWD. IPX clients and server stations may give up before the transition is done. This means that the first many connection attempts are lost. STP should not be enabled on ports that are intended for dedicated stations. This problem does not occur on shared media, because the port will stay attached to the hub even though all stations have closed.
Another reason for not enabling STP for dedicated stations is, that the whole network will go into Topology Change state each time a station opens or closes. This will cause the whole network to use short aging timers, which means that all address tables will be cleared. This can lead to many unknown station broadcasts before the tables converge again. Note that a port or CRF that is manually forced to either FWD or BLK state, is not participating in the spanning tree protocol. If a port or CRF is changed from Auto (the default) to FWD/BLK, it is the network administrator’s responsibility that no loops are created from this port(s) to other parts of the network.
SmartStack | Preparing for Installation |
