Intelligent Management: on demand router system and custom properties

We can use on demand router (ODR) custom properties to change the behavior of the ODR. For example, we can change the error code that the ODR returns when messages are rejected because of processor or memory overload.


http.log.history custom property

Use the http.log.history custom property to specify the number of history server log files. The server log files are the ODR custom log files, as well as the proxy.log, local.log, and cache.log files. Without this custom property, you have one history file for the server log files. Setting this custom property does not affect the custom logs that are already initialized.

Value Description
Scope ODR or ODR cluster
Value Any positive integer greater than 0
Default 1


http.log.history.backup.list custom property

By default, existing custom log files from previous runs are not counted towards the maximum number of history files. Set the http.log.history.backup.list proxy custom property to true so that the ODR counts existing custom logs towards the maximum number of history files.

Scope ODR or ODR Cluster
Value Any positive integer greater than 0
Default 1


http.log.maxSize custom property

Use the http.log.maxSize custom property to specify the maximum log size in megabytes (MB). A value of UNLIMITED indicates unlimited. As with the http.log.history custom property, the http.log.maxSize custom property applies to the ODR custom log files, as well as the proxy.log, local.log, and cache.log files

Value Description
Scope ODR or ODR cluster
Value Any positive integer greater than 0
Default 25 MB


CenterCell custom property

When you are configuring multi-cell performance management in the environment, we can use the CenterCell custom property to designate one cell as the center cell. You also set the CenterCell custom property individually for each cell to designate as a point cell.

Avoid trouble: One and only one custom property should be set to true.gotcha

Value Description
Scope Cell
Valid values true: Designates one cell as the center cell

false: Designates one cell as a point cell


ODR.heapUsage.max

Use the ODR.heapUsage.max custom property to configure a percentage value that determines at what amount of heap usage the ODR rejects requests. If heap usage exceeds 90%, the ODR rejects any incoming request and a 503 error code is returned.

Value Description
Scope Cell
Value Percentage
Default 90%


ODR.heapUsage.algorithm

Use the ODR.heapUsage.algorithm custom property to configure when heap usage is calculated. If we set the value to globalGC, the amount of heap usage is calculated only immediately after a global garbage collection cycle. If we set the value to request, the amount of heap usage is calculated with each request.

Value Description
Scope Cell
Value Algorithm
Default globalGC


ODR.heapUsage.errorCode

Use the ODR.heapUsage.errorCode custom property to configure the type of error code returned when a request is received and the heap usage exceeds the maximum threshold.

Value Description
Scope Cell
Value Integer
Default 503


ODR.sslAlias.<cluster_name>

Use the ODR.sslAlias.<cluster_name> custom property to specify the SSL alias name to be used during SSL outbound connections to any of the servers in the specified cluster. Set this custom property at cell level. Restart the ODR in order for this custom property setting to take effect.


http.overload.error

Use the http.overload.error custom property to configure a custom error code for the autonomic request flow manager to return when an HTTP message over TCP or SSL is rejected due to processor or memory overload. If we do not configure this custom property, the default 503 error code is returned.

Value Description
Scope On demand router
Value Integer
Default 503


sip.overload.error

Use the sip.overload.error custom property to configure a custom error code for the autonomic request flow manager to return when a Session Initiation Protocol(SIP) message over Transmission Control Protocol (TCP) or SSL is rejected because of processor or memory overload. If we do not configure this custom property, the default 503 error code is returned.

Value Description
Scope On demand router
Value Integer
Default 503


sipu.overload.error

Use the sipu.overload.error custom property to configure a custom error code for the autonomic request flow manager to return when a Session Initiation Protocol(SIP) message over User Datagram Protocol (UDP) is rejected due to processor or memory overload. If we do not configure this custom property, the default 503 error code is returned.

Value Description
Scope On demand router
Value Integer
Default 503


http.partialResponseBodyBufferSize

Use the http.partialResponseBodyBufferSize custom property to disable the ODR from buffering the size of the response payload when you perform a rollout on an application edition. Set the http.partialResponseBodyBufferSize custom property to a value of 0.

Value Description
Scope On demand router
Value Integer
Default 0


System properties

Follow the instructions to set specific system properties for the ODR.

From the console, select Servers > On demand routers > on_demand_router > Java and Process Management > Process definition > Java Virtual Machine.


ODCLeftGroupDelay

Use the ODCLeftGroupDelay =0 system property set to allow no delay for on demand configuration detection of down servers during failover when servers become unavailable.


ODR.traceRouteHeader

Use the ODR.traceRouteHeader system property on the ODR, and it will add a response header with the route that the request took.

For example, -DODR.traceRouteHeader=TraceRoute adds a response header with the name TraceRoute to each request. The value of this response header is the path that the request took.


updateWLM

When false, the DWLM controller will not update the calculated weights for the cluster members in the Work Load Management (WLM). The default value of this property is true. Cell recycle is required for this custom property to take effect. IBM recommends that updateWLM is set to false when HAManager is turned off through out the cell or on all the dynamic cluster members.

This custom property can be set at dynamic cluster level and cell level:

Value Description
Scope Dynamic cluster or cell
Valid values true or false
Default true


Related concepts

  • Overview of request flow prioritization


    Related tasks

  • Configure ODRs
  • Configure multi-cell performance management: Star Topology
  • Set up Intelligent Management for dynamic operations
  • Create ODRs
  • Create ODRs
  • Configure SSL offload for all HTTPS traffic
  • Performing a rollout on an edition

  • createodr.jacl script

    Reference topic