IBM 990 - Manual (Page 255)

Appendix A. Hardware Management Console (HMC) 243
Additional connections to the Ethernet LAN
These may be made to expand the connectivity beyond the local HMC and SE (not applicable
to systems with FC 0075).
This scenario is shown in Figure A-8. If connections to previous generations of Enterprise
Server systems are desired, they may be connected using Ethernet-to-token ring bridges.
If connection to the enterprise LAN is desired, it is recommended that an Ethernet bridge or
router be installed to isolate the HMC and SE from other systems.
Figure A-8 Ethernet only - two-path wiring scenario with additional connections
Token ring and Ethernet wiring scenario
The token ring and Ethernet wiring scenario, shown in Figure A-9 on page 244, is intended for
enterprises that have both token ring wiring and Ethernet wiring requirements. This scenario
is included to provide the possibility of controlling the Support Elements from both a token
ring Hardware Management Console and an Ethernet Hardware Management Console at the
same time.
This wiring scenario is supported by the default set of adapters available with the Support
Elements and the token ring adapter on the Hardware Management Console. The token ring
adapter assumes the use of a 16 Mb token ring facility. The Ethernet features assume the
use of 10/100 Mb Ethernet facilities, requiring the use of CAT-5 Ethernet cabling.
For this scenario, the three communication protocols (SNA, TCP/IP, and NetBios) used in
Support Element-to-Hardware Management Console communication are defined for both the
token ring and the Ethernet adapters of the Support Elements. The token ring wiring is
connected using the MAU as described in “Token ring only wiring scenario” on page 238. The
Ethernet wiring is connected from the Support Elements to a customer-supplied local hub
capable of 10/100 Mb Ethernet rates.
The Hardware Management Consoles attached to either LAN will be able to automatically
discover the Support Elements, assuming that the LAN network allows NetBios to flow
Primary
Ethernet LAN
Secondary
Ethernet LAN
Token-Ring Token-Ring
LAN LAN
zSeries 990
Enterprise
LAN
SE
SE
zSeries 990
SE
SE
Bridge Bridge