IBM SG24-5131-00 사용자 설명서

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IBM Certification Study Guide  AIX HACMP
  • SP Switch is a high-speed packet switching network, running on the 
RS/6000 SP system only. It runs bidirectionally up to 80 MBps, which adds 
up to 160 MBps of capacity per adapter. This is node-to-node 
communication and can be done in parallel between every pair of nodes 
inside an SP. The SP Switch network has to be defined as a private 
Network, and ARP must be enabled. This network is restricted to one 
adapter per node, thus, it has to be considered as a Single Point Of 
Failure. Therefore, it is strongly recommended to use AIX Error 
Notification to propagate a switch failure into a node failure when 
appropriate. As there is only one adapter per node, HACMP uses the 
ifconfig alias addresses for IPAT on the switch; so, a standby address is 
not necessary and, therefore, not used on the switch network. Hardware 
address swapping also is not supported on the SP Switch.
For IP Address Takeover (IPAT), in general, there are two adapters per 
cluster node and network recommended in order to eliminate single points of 
failure. The only exception to this rule is the SP Switch because of hardware 
limitations.
2.2.2  Non-TCPIP Networks
Non-TCP/IP networks in HACMP are used as an independent path for 
exchanging messages or heartbeats between cluster nodes. In case of an IP 
subsystem failure, HACMP can still differentiate between a network failure 
and a node failure when an independent path is available and functional. 
Below is a short description of the three currently available non-TCP/IP 
network types and their characteristics. Even though HACMP works without 
one, it is strongly recommended that you use at least one non-TCP/IP 
connection between the cluster nodes.
2.2.2.1  Supported Non-TCP/IP Network Types
Currently HACMP supports the following types of networks for non-TCP/IP 
heartbeat exchange between cluster nodes:
  • Serial (RS232) 
  • Target-mode SCSI
  • Target-mode SSA
All of them must be configured as Network Type: serial in the HACMP 
definitions.