This Knowledgebase article provides information about configuring rules in Neverfail Continuity Engine.
Rules are implemented by plug-ins (there are no user-defined rules). Rules can be either timed (they must evaluate as true continuously for the specified duration to trigger) or latched (they trigger as soon as they evaluate to true). Rules can be configured with rule actions, which are the tasks to perform when the rule triggers.
Rules use the following control and decision criteria for evaluation:
- Name: (the name of the rule)
- Enabled: (whether the rule is enabled or not)
- Condition: (the condition being evaluated)
- Duration: (the length of time the condition exists before triggering the failure action)
- Interval: (the length of time between failure actions)
- First Failure: (action to take upon first failure) The default is set to Log Warning
- Second Failure: (action to take upon second failure) The default is set to Log Warning
- Third Failure: (action to take upon third failure) The default is set to Log Warning.
The Applications: Rules page provides a list of rules with their current status, and two ways to edit and check rules.
Check a Rule Condition
To check a rule condition, select the rule in the Rules list and perform the following:
- Click Check Now at the lower right of the page.
Neverfail Engine immediately checks the rule conditions of the current configuration against the attributes of the system and application.
Edit a Rule
Rules are implemented by plug-ins and cannot be created by users. Each plug-in contains a default set of rules with options that may be modified by the user.
To Edit a rule:
- To edit a rule, select the rule in the Rules list.
- Click Edit at the lower right of the page.
The Edit Rule dialog appears. Use this dialog to Enable or Disable a Rule, set the specific options for the Rule, and to assign tasks to perform On First Failure, On Second Failure, and On Third Failure. The following tasks can be assigned in the event of a failure:
- Restart Applications – Restarts the protected application
- Log Warning – Adds an entry to the logs
- Switchover – Initiates a switchover to the currently passive server
- Rule Action – Executes the command or script previously defined as a Rule Action task under the Application: Tasks tab.
Note: If the installed servers are in a virtual-to-virtual configuration, the following additional tasks are available as a result of the vSphere Integration Plug-in.
- vSphere Integration\RestartVM — Cleanly shuts down and restarts the Windows OS on the target VM
- vSphere Integration\TriggerMigrateVM — Depending on the parameters specified it can be vMotion, enhanced vMotion or storage vMotion
- vSphere Integration\TriggerMigrateVMandRestartApplication — Same as TriggerMigrateVM + application restart
- vSphere Integration\TriggervSphereHaVmReset — Hard Reset of the VM implemented by integration with VMware HA
Note: This option requires vSphere HA Application monitoring for the cluster and VM.
- When all options are selected, click OK to accept changes and dismiss the dialog.
Neverfail Continuity Engine