Station Mode (Das And Sas); Single Attachment Station (Sas); Dual Attachment Stations; Sample Fddi Configurations - 3Com corebuilder 3500 Implementation Manual

Station Mode (DAS
and SAS)
Single Attachment
Station (SAS)
Dual Attachment
Stations
Sample FDDI
Configurations
You can modify the FDDI station mode that is assigned to a specific port
number to either DAS (Dual Attachment Station) or SAS (Single
Attachment Station) S port or M port. For the new station mode to take
effect, you must reboot your system.
If you configure the FDDI ports as single-attached stations, each port is
selectable as a bridge port. You can select your SAS ports to be either S or
M ports.
If you configure the FDDI ports as dual-attached stations, you must
specify the lowest-numbered (anchor) port in the DAS pair. The other port
becomes unselectable.
Effect and Consequence
When you set the station mode, consider the following:
When you modify the station mode, any FDDI ports that are
associated with a VLAN or a trunk are removed from the VLAN or
trunk.
You can install your system into many possible FDDI configurations.
Figure 18 shows systems attached to an FDDI dual ring. The connection
to the dual ring is made by the A and B ports on the system. DASs,
excluding concentrators, may be attached to the dual ring, as shown.
CAUTION: 3Com strongly recommends that you connect equipment that
can be turned on and off, such as workstations, only through
concentrators. Connect intermediate systems that are seldom turned off,
such as bridges and routers, to the FDDI dual ring only if they are
equipped with an optical bypass switch. These precautions protect the
integrity of the dual ring.

Station Mode (DAS and SAS)

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