Dynamic cluster settings
Use this page to view configurations of existing dynamic
clusters.
To view this administrative console page, click .
You must have monitor privileges to view the
configuration of existing dynamic clusters.
- Name
Specifies a name for the dynamic cluster. The name for
a dynamic cluster must be unique among all the clusters in the cell.
The name field cannot contain the following characters: #
\ / , : ; " * ? < > | = + & % ' .
The name cannot begin with a period (.) or
a space. A space does not generate an error, but leading and trailing
spaces are automatically deleted.
- Type
Specifies the type of servers that are being used in the
dynamic cluster.
The following list contains the server types:
- WebSphere Application Server
- Specifies that the dynamic cluster contains application servers
that are running WebSphere Application Server or WebSphere Virtual
Enterprise.
- Apache server
- Specifies that the dynamic cluster contains Apache servers.
- Custom HTTP server
- Specifies that the dynamic cluster contains HTTP servers.
- JBoss server
- Specifies that the dynamic cluster contains servers that are running
JBoss Application Server.
- On demand router
- Specifies that a dynamic cluster of on demand routers is being created.
- PHP server
- Specifies that the dynamic cluster contains servers that are running
PHP.
- Apache Tomcat server
- Specifies that the dynamic cluster contains servers that are running
Apache Tomcat.
- WebSphere Application Server Community Edition server
- Specifies that the dynamic cluster contains servers that are running
WebSphere Application Server Community Edition.
- BEA WebLogic server
- Specifies that the dynamic cluster contains servers that are running
BEA WebLogic.
- External WebSphere application servers
- Specifies that the dynamic cluster contains servers that are in
other cells. These cells might be running other versions of WebSphere
Application Server, such as Version 5.1 or 6.0. You can map these
static clusters to a dynamic cluster.
- Number of running instances
Specifies an automatically generated value that is based
on the number of server instances that are running for the dynamic
cluster.
For example, a dynamic cluster might have three applications running,
with two instances running on each of the four members of the dynamic
cluster. The number of instances is 8.
- Operational mode
Specifies the level that the dynamic cluster interacts
with the dynamic operations environment:
- Manual: In manual mode, the dynamic cluster
is no different than the normal application server environments with
static clusters. No interaction with the dynamic operations environment
occurs.
- Supervised: In supervised mode, the WebSphere
Virtual Enterprise environment provides information and recommendations
for actions that the administrator can use.
- Automatic: In automatic mode, the WebSphere
Virtual Enterprise environment takes actions automatically. In automatic
mode, the dynamic operations environment handles placements and provisioning.
You can change the operational mode in the administrative console
by clicking .
- Enable failover of transaction log recovery
Specifies that for the transaction service component, failover
of the transaction log for recovery purposes is enabled or disabled.
This field is valid for WebSphere application server dynamic clusters
only.
The default is disabled. If you enable this setting, the transaction
service properties that are required for peer recovery of failed applications
must be properly configured. If these properties are configured, failover
recovery of the transaction log occurs if the server processing the
transaction log fails. If the transaction services properties that
are required for peer recovery of failed application servers in a
cluster are not properly configured, this setting is ignored.
- Membership policy
Specifies an expression that is used to define which nodes
are used for the dynamic cluster. This option displays only if you
choose to automatically define cluster members with rules. This option
does not display if you choose to manually define your cluster members.
Use the subexpression
builder to build a Membership policy.
The membership policy specifies which nodes are members of the dynamic
cluster. Click Preview membership to view which
nodes are in the dynamic cluster with the membership policy that you
defined.
Example
- To define membership as all nodes in a specific node group:
node_nodegroup = 'my_node_group'
- To define membership as all nodes that run Apache:
node_property$APACHE_2_0 IS NOT NULL
- To define membership as all nodes that run Apache and PHP:
node_property$APACHE IS NOT NULL and node_property$PHP IS NOT NULL
- To define membership as all nodes that run
WebSphere Application Server Community Edition Version 2.0 or later:
node_property$WASCE_2.0* IS NOT NULL
- To define membership as all nodes that run
WebSphere Application Server Community Edition Version 2.0 only:
node_property$WASCE_2.0 IS NOT NULL
- To define membership as all nodes that have a name that is like my_node,
including my_node_1, my_node_2, and so on:
node_name like 'my_node%'
- To define membership as a list of specific host names:
node_hostname in ('node1.mydomain.com','node2.mydomain.com')
You can group subexpressions by using
and,
or,
or
not logical operators and parenthesis. The following example
defines node membership as nodes that are not in the my_node_group
node group, and have a name that is like
my_node, including
my_node_1,
my_node_2,
and so on.
not (node_nodegroup='my_node_group') and node_name like 'my_node%'
- Minimum number of cluster instances
Specifies the minimum number of running instances for the
dynamic cluster. If a minimum value is excessive, performance degradation
might occur.
- If you want to stop instances when no activity exists, click Stop
all instances during periods of inactivity. If you select
this option, enter the Time to wait before stopping instances value
in minutes.
Restriction: If you are routing Session Initiation Protocol
(SIP) traffic to the dynamic cluster, do not use the If
other dynamic clusters need resources, stop all instances of this
cluster during periods of inactivity option. Use one of
the options that keep at least one cluster member active at all times.
- If you want one cluster instance started at all times, click Keep
one instance started at all times. This option is the
default.
- If you want more than one cluster instance started at all times,
click Keep multiple instances started at all times.
If you select this option, enter the Number of instances that
you want started at all times.
- Maximum number of cluster instances
Specifies the maximum number of cluster instances that
can start.
- If you want to limit the number of cluster instances, click Limit
the number of instances that can start, and enter the
maximum Number of instances.
- If you do not want to limit the number of cluster instances, click Do
not limit the number of instances that can start.
- Vertical stacking of instances on a node
Specifies if more than one instance can start on a single
node. By configuring vertical stacking, the application placement
controller can start more than one instance of the dynamic cluster
on the node when a large workload exists.
Use vertical stacking to improve bottleneck conditions
between applications. Select Allow more than one instance
to start on the same node, and type the Number
of instances value. The number of instances is the number
of application servers for a cluster that are needed to use all the
power of a node. Also, the number you choose for vertical stacking
is the number of servers that are automatically created.
If you use target nodes for vertical stacking
that are at an older product version than the deployment manager version,
adding new members on the same node is disabled. Vertical stacking
is available only on application servers, WebSphere Application
Server Community Edition servers, and PHP servers that have cluster
members that are automatically defined by rules.
- Isolation preference
Specifies if you want the dynamic
cluster to run on the same nodes as other instances of dynamic clusters,
or if you want the dynamic cluster to be the only dynamic cluster
that is running on a node. This option is available if you choose
to automatically define your cluster members with rules. If
you manually define your cluster members, you do not have the option
to enable dynamic cluster isolation.
- Select No isolation requirements if cluster
instances in this dynamic cluster can run on the same node as other
instances from different dynamic clusters. This option is the default.
- Select Strict isolation if cluster instances
in this dynamic cluster can run only with other instances of the same
dynamic cluster on the same node.
- Select Associate with an isolation group if
the cluster instance can run with any other instance of a dynamic
cluster that is in the same shared group on the same node. Specify
an Isolation group name value. To create a
new isolation group for this dynamic cluster, type a unique name.
To select from a list of the existing isolation groups, click Browse.
A topology of the current isolation groups is displayed. Click an
isolation group name to select the group.
dc_detail_main