IBM Computer Hardware User Manual page 37

Note: Either eth0 or eth1 can be a DHCP server on the HMC.
The managed system will be automatically visible on the HMCs. This is our
recommended way to do high availability with HMCs. It is supported by all
POWER5 systems.
Two HMCs on the same network, using static IP addresses is shown in
Figure 23.
HMC1
T1
P5 Managed
System*
Fix IP-Address
* p575, p590 and p595 do not support fix IP addresses
Figure 23 HMCs connected to the FSP using 1 network and static IP addresses
In Figure 23, all systems HMCs and CECs have their own fixed IP-address. So
you do not need to consider in which sequence they has to be started.
Important: For p5-575, p5-590, and p5-595 systems, fixed IP-addresses are
not supported. You have to use the DHCP server.
The fixed IP-address can be set by launching the ASMI menu. Please refer to
"APPENDIX" on page 40 to get more information on how to launch the ASMI
menu.
Hardware Management Console (HMC) Case Configuration Study for LPAR Management
HMC2
T1
P5 Managed
System*
Fix IP-Address
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