IBM SG24-5131-00 사용자 설명서
Cluster Planning
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If you do not use Hardware Address Takeover, the ARP cache of clients can
be updated by adding the clients’ IP addresses to the
be updated by adding the clients’ IP addresses to the
PING_CLIENT_LIST
variable in the /usr/sbin/cluster/etc/clinfo.rc file.
2.4.4 NFS Exports and NFS Mounts
There are two items concerning NFS when doing the configuration of a
Resource Group:
Resource Group:
Filesystems to Export
File systems listed here will be NFS exported,
so they can be mounted by NFS client
systems or other nodes in the cluster.
so they can be mounted by NFS client
systems or other nodes in the cluster.
Filesystems to NFS mount
Filling in this field sets up what we call an
NFS
cross mount. Any file system defined in this
field will be NFS mounted by all the
participating nodes, other than the node that is
currently holding the resource group. If the
node holding the resource group fails, the next
node to take over breaks its NFS mount for
this file system, and mounts the file system
itself as part of its takeover processing.
field will be NFS mounted by all the
participating nodes, other than the node that is
currently holding the resource group. If the
node holding the resource group fails, the next
node to take over breaks its NFS mount for
this file system, and mounts the file system
itself as part of its takeover processing.
2.5 Application Planning
The central purpose for combining nodes in a cluster is to provide a highly
available environment for mission-critical applications. These applications
must remain available at all times in many organizations. For example, an
HACMP cluster could run a database server program that services client
applications. The clients send queries to the server program that responds to
their requests by accessing a database that is stored on a shared external
disk.
available environment for mission-critical applications. These applications
must remain available at all times in many organizations. For example, an
HACMP cluster could run a database server program that services client
applications. The clients send queries to the server program that responds to
their requests by accessing a database that is stored on a shared external
disk.
Planning for these applications requires that you be aware of their location
within the cluster, and that you provide a solution that enables them to be
handled correctly, in case a node should fail. In an HACMP for AIX cluster,
these critical applications can be a single point of failure. To ensure the
availability of these applications, the node configured to take over the
resources of the node leaving the cluster should also restart these
applications so that they remain available to client processes.
within the cluster, and that you provide a solution that enables them to be
handled correctly, in case a node should fail. In an HACMP for AIX cluster,
these critical applications can be a single point of failure. To ensure the
availability of these applications, the node configured to take over the
resources of the node leaving the cluster should also restart these
applications so that they remain available to client processes.
To put the application under HACMP control, you create an application server
cluster resource that associates a user-defined name with the names of
specially written scripts to start and stop the application. By defining an
application server, HACMP for AIX can start another instance of the
cluster resource that associates a user-defined name with the names of
specially written scripts to start and stop the application. By defining an
application server, HACMP for AIX can start another instance of the