Network Allocations On The 8260 Backplane; Backplane Path Display For Fddi Segments - IBM Nways 8260 Manual

An example of the output from this command is shown in Figure 8 on page 23.
Figure 8. Backplane Path Display for FDDI Segments
The number of FDDI paths used by a single FDDI network on the Enhanced
TriChannel equals the number of FDDI modules on that network.
The FDDI paths on the Enhanced TriChannel use the same pins on the backplane
as are used by the Ethernet and/or token-ring segments. In Figure 8, the FDDI
paths shown as in use are those backplane pins which are used by other
segment types (that is, token-ring and/or Ethernet). Also, note that in this
example, we had no FDDI modules installed in our 8260.
On the ShuntBus, in addition to the two dedicated Ethernet segments, there can
be up to 4 FDDI segments. Unlike, the Enhanced TriChannel, there is no concept
of FDDI paths on the ShuntBus. Instead, there are 4 FDDI networks, each using
14 pins. The FDDI segments on the ShuntBus use the same pins as the
token-ring segments.

2.5 Network Allocations on the 8260 Backplane

As we now have so many options of switching modules and ports between
networks it is perhaps a good time to clarify the rules regarding those
allocations.
8260> show backplane_paths fddi
Physical Path
---------------
FDDI_PATH_8250_1
FDDI_PATH_8250_2
FDDI_PATH_8250_3
FDDI_PATH_8250_4
FDDI_PATH_8250_5
FDDI_PATH_8250_6
FDDI_PATH_8250_7
FDDI_PATH_8250_8
8260>
8250 Ethernet ports or modules can be connected to parallel addressed
segments (ethernet_1 thru 3 on the Enhanced TriChannel) only.
8250 Ethernet ports or modules cannot be connected to serially addressed
segments (ethernet_4 thru 8) on either the TriChannel or ShuntBus.
8260 Ethernet ports or modules can be connected to any of the segments
(ethernet_1 thru 8) on the TriChannel or ShuntBus. When connected to
ethernet_1 thru 3, they use parallel addressing and when connected to
ethernet_4 thru 8 they use serial addressing.
8250 token-ring or FDDI modules can only be connected to the segments on
the Enhanced TriChannel. They cannot be connected to the segments on the
ShuntBus.
8260 token-ring (or future 8260 FDDI) modules cannot be connected to any
segment on the Enhanced TriChannel. They can only be connected to the
segments on the ShuntBus.
Logical Network
---------------
in use
in use
in use
in use
in use
in use
in use
available
Chapter 2. Backplane Architecture
23