Digital Equipment DLE28-MA, Руководство пользователя

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SmartTrunk and the Configuration Screen
DLE28-MA User’s Guide 5-69
5. Do not loop front panel ports back to the same standalone device. If
the devices are modules residing in a chassis, then you cannot loop
back to the same module in the same chassis or to different modules
within that chassis. This includes all backplane interfaces that may
display on the SmartTrunk Configuration screen.
6. You must enable Spanning Tree before enabling SmartTrunk.
Spanning Tree will ‘block’ any ports not used by SmartTrunk that are
looped. This can include NETWORK and USER ports. The reason for
the blocking of a NETWORK port is that the port at the other end of
the link may be configured as a USER port.
Other Considerations
• If a network loop exists and SmartTrunk becomes disabled, and
Spanning Tree is operational, then the Spanning Tree Algorithm will
respond and block the necessary ports.
• If SmartTrunk becomes disabled, and a network loop exists, and
Spanning Tree is not-operational (disabled), then an infinite data-loop
occurs, taking down the network.
• If a port is disabled and as a result SmartTrunk is no longer active, then
all traffic is redirected over the remaining port(s).
• If three or more interface modules, such as the DLE28-MA, or
standalone devices are connected together in a loop condition and all
the ports that connect the loop are set to “NETWORK,” the results are
unpredictable. In this case all ports are assigned as “NETWORK”
ports and none are configured as “USER” ports. This is deemed an
illegal configuration.
• If a network loop exists when a port is disabled, then SmartTrunk will
reconfigure the remaining ports and continue to distribute traffic.