IBM Power 750 Technical Overview And Introduction page 112

For the HMC to communicate properly with the managed server, eth0 of the HMC must be
connected to either the HMC1 or HMC2 port of the managed server, although other network
configurations are possible. You can attach a second HMC to HMC2 port of the server for
redundancy. These must be addressed by two separate subnets. Figure 2-30 shows a simple
network configuration to enable the connection from HMC to server and to enable dynamic
LPAR operations. For more details about HMC and the possible network connections, see
IBM Power Systems HMC Implementation and Usage Guide, SG24-7491 (previous edition
was named Hardware Management Console V7 Handbook, SG24-7491).
Figure 2-30 HMC to service processor and LPARs network connection
The default mechanism for allocation of the IP addresses for the service processor HMC
ports is dynamic. The HMC can be configured as a DHCP server, providing the IP address at
the time that the managed server is powered on. In this case, the FSPs are allocated an IP
address from a set of address ranges that are predefined in the HMC software. These
predefined ranges are identical for version 7 R7.1.0 of the HMC code and for previous
versions.
If the service processor of the managed server does not receive a DHCP reply before time
out, predefined IP addresses will be set up on both ports. Static IP address allocation is also
an option. You can configure the IP address of the service processor ports with a static IP
address by using the Advanced System Management Interface (ASMI) menus.
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IBM Power 750 and 760 Technical Overview and Introduction
eth1
eth0
HMC
Management LAN
entx
LPAR
HMC1 1
Service
Processor
HMC2
Power Systems server
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