Oracle SOA Suite 11g has some great features to recover faulted instances automatically. When a BPEL process flow errors out, it is retried with all its invocations. This is undesirable in some cases. For example if re-calling a composite results in duplicated data, data have been changed before the recovery is planned to be executed or you do not want to create too many composite instances in order to save the space in your SOAINFRA-schema. See below the different places where automatic recoveries are configured / disabled.
1) Change RecurringScheduleConfig (see also the screenshot below)
- Right-click soa-infra (SOA_cluster_name)
- Choose SOA Administration > BPEL Properties
- Click "More BPEL Configuration Properties"
- Click "Recovery Config"
- Change values for RecurringScheduleConfig
- maxMessageRaiseSize = 0
- startWindowTime = 00:00
- stopWindowTime = 00:00
- Click Apply
2) Change StartupScheduleConfig (see also the screenshot below)
- Right-click soa-infra (SOA_cluster_name)
- Choose SOA Administration > BPEL Properties
- Click "More BPEL Configuration Properties"
- Click "Recovery Config"
- Change values forStartupScheduleConfig
- maxMessageRaiseSize = 0
- startupRecoveryDuration = 0
- subsequentTriggerDelay = 0
- Click Apply
The properties startWindowTime and stopWindowTime specify the period during which Auto Recovery is active. By default auto recovery feature will be active from 12AM to 4AM everyday (remember that it’s SOA server time), shown in above screenshot. We can change these settings by simply updating the time values in 24 hr format and do click on Apply.
The property maxMessageRaiseSize specifies the number of messages to be sent in each recovery attempt, in effect resembles the batch size.
The property subsequentTriggerDelay specifies interval between consecutive auto recovery attempts and the value is 300 sec by default.
The property threshHoldTimeInMinutes is used by BPEL engine, to mark particular instance eligible for auto recovery once the recoverable fault occurs which is 10 min by default.
If we observe closely, none of these properties mention about number of recovery attempts to be made which is altogether a separate MBean property. To set, navigate to soa-infra -> SOA Administration -> BPEL Properties -> More BPEL Configuration Properties -> MaxRecoverAttempt. The default value is 2.
To disable ‘Auto Recovery’, set the maxMessageRaiseSize property value to 0.
3) Change GlobalTxMaxRetry
The property GlobalTxMaxRetry specifies how many retries are performed if an error is identified as a retriable one. For example, after several web service invocations, if dehydration fails due to a data source error, then this is identified as a retriable error and all activities from the prior dehydration state are retried. If the activities being retried are not idempotent (that is, their state can change with each retry and is not guaranteed to give the same behavior), then multiple retries can be problematic.
You can set GlobalTxMaxRetry to 0 in the Systems MBean Browser.
- Right-click soa-infra (SOA_cluster_name)
- Choose SOA Administration > Common Properties
- Click "More SOA Infra Advanced Configuration Properties"
- Click "GlobalTxMaxRetry"
- In the Value field, enter an appropriate value
- Click Apply
BPEL Recovery Console:
Navigate to soa-infra -> Service Engines -> BPEL -> Recovery to view the recoverable instances. Note that, the console shows all recoverable instances irrespective of enabled/disabled ‘Auto Recovery’. We can manually recover the faulted instances from this console when Auto recovery is not enabled.
Auto Recovery Behavior:
Whenever a recoverable fault (this term is more abstract, I verified this behavior with Remote, Binding and User Defined Faults) occurs during the BPEL processing, it will be visible in Recovery console. If Auto Recovery is enabled, after threshHoldTimeInMinutes BPEL runtime will try to auto recover the instance. If it’s not successful, again number of recovery attempts will be made as given for MaxRecoverAttempt with an interval as given for subsequentTriggerDelay. If instance fails even after these maximum recover attempts, the instance will be marked as exhausted (can be queried on recovery console using message state as exhausted). We can use ‘Reset’ button to make these instances eligible for Auto Recovery again.
Note that, we observe this behavior only when the fault is thrown back to BPEL runtime or fault is not caught within BPEL process.
No comments:
Post a Comment