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WebLogic Server Configuration Reference

# Cluster

# Description

This bean represents a cluster in the domain. Servers join a cluster by calling ServerMBean.setCluster with the logical name of the cluster. A configuration may define zero or more clusters. They may be looked up by logical name. The name of a cluster denotes its logical cluster name.

# Syntax

>     <Cluster
>       ClientCertProxyEnabled=( "true" | "false" )
>       ClusterAddress="String"
>       DefaultLoadAlgorithm=( "round-robin" | "weight-based" | "random" | "round-robin-affinity" | "weight-based-affinity" | "random-affinity" )
>       FrontendHTTPPort="number"
>       FrontendHTTPSPort="number"
>       FrontendHost="String"
>       HttpTraceSupportEnabled=( "true" | "false" )
>       IdlePeriodsUntilTimeout="number"
>       MulticastAddress="String"
>       MulticastBufferSize="number of kilobytes"
>       MulticastPort="number"
>       MulticastSendDelay="number"
>       MulticastTTL="number"
>       Name="String"
>       Notes="String"
>       WeblogicPluginEnabled=( "true" | "false" )
>     />

# Parent Elements

- Domain

# Attributes

Table 4-1 Cluster attributes

Attribute | Description | Range of Values and Default
--- | --- | ---
ClientCertProxyEnabled | A value of `true` causes proxy-server plugins to pass identity certificates from clients to all web applications that are deployed on all server instances in the cluster. A proxy-server plugin encodes each identify certification in the `WL-Proxy-Client-Cert` header and passes the header to WebLogic Server instances. Each WebLogic Server instance takes the certificate information from the header, trusting that it came from a secure source, and uses that information to authenticate the user. If you specify `true`, use a weblogic.security.net.ConnectionFilter to ensure that each WebLogic Server instance accepts connections only from the machine on which the proxy-server plugin is running. Specifying `true` without using a connection filter creates a potential security vulnerability because the `WL-Proxy-Client-Cert` header can be spoofed. A value of `true` overrides the value that each server instance within the cluster specifies with ServerMBean#setClientCertProxyEnabled(boolean). By default (or if you specify `false`): Each server instance can determine whether its applications trust certificates sent from the proxy server plugin. If a server instance does not set a value for its `ClientCertProxyEnabled` attribute (or if it specifies `false`), the `weblogic.xml` deployment descriptor for each web application determines whether the web application trusts certificates sent from the proxy server plugin. By default (or if the deployment descriptor specifies `false`), users cannot log in to the web application from a proxy server plugin. | Admin Console field label: Client Cert Proxy Enabled Default: false Secure value: false
ClusterAddress | Defines the address to be used by clients to connect to this cluster. This address may be either a DNS host name that maps to multiple IP addresses or a comma separated list of single address host names or IP addresses. If network channels are configured, it is possible to set the cluster address on a per channel basis. | Admin Console field label: Cluster Address Required: no
DefaultLoadAlgorithm | Defines the algorithm to be used for load-balancing between replicated services if none is specified for a particular service. | Admin Console field label: Default Load Algorithm Required: no Default: round-robin
FrontendHTTPPort | Sets the FrontendHTTPPort for the default webserver (not virtual hosts) for all the servers in the cluster. Provides a method to ensure that the webapp will always have the correct PORT information, even when the request is coming through a firewall or a proxy. If this parameter is configured, the HOST header will be ignored and the information in this parameter will be used in its place, when constructing the absolute urls for redirects. | Admin Console field label: Frontend HTTPPort Default: 0
FrontendHTTPSPort | Sets the FrontendHTTPSPort for the default webserver (not virtual hosts) for all the servers in the cluster. Provides a method to ensure that the webapp will always have the correct PORT information, even when the request is coming through a firewall or a proxy. If this parameter is configured, the HOST header will be ignored and the information in this parameter will be used in its place, when constructing the absolute urls for redirects. | Admin Console field label: Frontend HTTPSPort Default: 0
FrontendHost | Sets the HTTP FrontendHost for the default webserver (not virtual hosts) for all the servers in the cluster. Provides a method to ensure that the webapp will always have the correct HOST information, even when the request is coming through a firewall or a proxy. If this parameter is configured, the HOST header will be ignored and the information in this parameter will be used in its place, when constructing the absolute urls for redirects. | Admin Console field label: Frontend Host Required: no
HttpTraceSupportEnabled | Attackers may abuse HTTP TRACE functionality to gain access to information in HTTP headers such as cookies and authentication data. In the presence of other cross-domain vulnerabilities in web browsers, sensitive header information could be read from any domains that support the HTTP TRACE method. This attribute is for disabling HTTP TRACE support. It is duplicated both in ClusterMBean and ServerMBean so the attribute HttpTraceSupportEnabled can be used cluster-wide. ClusterMBean overrides ServerMBean | Default: false
IdlePeriodsUntilTimeout | Maximum number of periods that a cluster member will wait before timing out a member of a cluster. | Default: 3 Minimum: 3
MulticastAddress | Defines the multicast address used by cluster members to communicate with each other. | Admin Console field label: Multicast Address Required: no Default: 237.0.0.1
MulticastBufferSize | Defines the multicast socket send/receive buffer size. | Admin Console field label: Multicast Buffer Size Units: kilobytes Default: 64 Minimum: 64
MulticastPort | Defines the multicast port used by cluster members to communicate with each other. | Admin Console field label: Multicast Port Default: 7001 Minimum: 1 Maximum: 65535
MulticastSendDelay | Defines the number of milliseconds to delay sending message fragments over multicast in order to avoid OS-level buffer overflow. | Admin Console field label: Multicast Send Delay Default: 3 Minimum: 0 Maximum: 250
MulticastTTL | Sets the time-to-live value for the cluster's multicast address. | Admin Console field label: Multicast TTL Default: 1 Minimum: 1 Maximum: 255
Name | The name of this configuration. WebLogic Server uses an MBean to implement and persist the configuration. | Admin Console field label: Name Required: no
Notes | Optional information that you can include to describe this configuration. | Admin Console field label: Notes Required: no
WeblogicPluginEnabled | WLS HttpRequest.getRemoteAddr() used to rely on X-Forwarded-For for its returned value. This is a security hole due to HTTP header can be easily mocked and we end up with returning wrong value. This is improved by introducing a proprietary header WL-Proxy-Client-IP from our plugins and this header will only be used if WLS is configured to use our plugins. This is duplicated both in ClusterMBean and ServerMBean so the attribute WeblogicPluginEnabled can be used cluster-wide. ClusterMBean overrides ServerMBean | Admin Console field label: WebLogic Plug-In Enabled Default: false Secure value: false