IBM AIX HACMP, Hardware User Manual

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HACMP Installation and Cluster Definition
105
Adding or Changing Adapters after the Initial Configuration
If you want to change the information about an adapter after the initial
configuration, use the Change/Show an Adapter screen. See the chapter on
changing the cluster topology in the
HACMP for AIX, Version 4.3:
Administration Guide , SC23-4279, for more information.
4.2.4 Configuring Network Modules
Each supported cluster network in a configured HACMP cluster has a
corresponding cluster network module. Each network module monitors all I/O
to its cluster network.
The Network Modules are pre-loaded when you install the HACMP software.
You do not need to enter information in the Network Module SMIT screens
unless you want to change some field associated with a network module,
such as the failure detection rate.
Each network module maintains a connection to other network modules in the
cluster. The Cluster Managers on cluster nodes send messages to each other
through these connections. Each network module is responsible for
maintaining a working set of service adapters and for verifying connectivity to
cluster peers. The network module is also responsible for reporting when a
given link actually fails. It does this by sending and receiving periodic
heartbeat messages to or from other network modules in the cluster, and
reporting back to the Cluster Manager when it misses a threshold number of
heartbeats.
Currently, network modules support communication over the following types
of networks:
• Serial (RS232)
• Target-mode SCSI
• Target-mode SSA
• IP (Generic IP)
• Ethernet
• Token-Ring
• FDDI
• SOCC
When IPAT is configured, the run level of the IP-related entries (e. g.
rctcpip, rcnfs...) of the
/etc/inittab
are changed to “
a
”. This has the result
that these services are not started at boot time, but with HACMP.
Note