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Product: Cluster Server Guides   
Manual: Cluster Server 4.1 Agent Developer's Guide   

Agent Attribute Definitions

Each agent attribute is listed and defined in the following sections.

ActionTimeout

After the hares -action command has instructed the agent to perform a specified action, the action entry point has the time specified by the ActionTimeout attribute (scalar-integer) to perform the action. The value of ActionTimeout may be set for individual resources. The default is 40 seconds. The ActionTimeout attribute value can be overridden.

AgentFile

The default name of the agent file to be executed is:

$VCS_HOME/bin/resource_type/resource_typeAgent.

The AgentFile attribute value cannot be overridden.

AgentReplyTimeout

The engine restarts the agent if it has not received the periodic heartbeat from the agent for the number of seconds specified by this attribute. The default value of 130 seconds works well for most configurations. Increase this value if the engine is restarting the agent. This may occur when the system is heavily loaded or if the number of resources exceeds three or four hundred. (See the command haagent -display in the chapter on administering VCS from the command line in the VERITAS Cluster Server User's Guide.) Note that the engine will also restart a crashed agent. The AgentReplyTimeout attribute value cannot be overridden.

AgentStartTimeout

After the engine has started the agent, this is the amount of time the engine waits for the initial agent "handshake" before attempting to restart. Default is 60 seconds. The AgentStartTimeout attribute value cannot be overridden.

ArgList

An ordered list of attributes whose values are passed to the open, close, online, offline, monitor, and clean entry points. Default is empty list. The ArgList attribute value cannot be overridden.

ArgList Reference Attributes

Reference attributes refer to attributes of a different resource. If the value of a resource attribute is defined as the name of another resource, the ArgList of the first resource can refer to an attribute of the second resource using the : operator.

For example, if the resource ArgList resembles the following code sample (in which the value of attr3 is the name of another resource), the entry points are passed the values of the attr1, attr2 attributes of the first resource, and the value of the attr_A attribute of the second resource.


 { attr1, attr2, attr3:attr_A }

AttrChangedTimeout

Maximum time (in seconds) within which the attr_changed entry point must complete or else be terminated. Default is 60 seconds. The AttrChangedTimeout attribute value can be overridden.

CleanTimeout

Maximum time (in seconds) within which the clean entry point must complete or else be terminated. Default is 60 seconds. The CleanTimeout attribute value can be overridden.

CloseTimeout

Maximum time (in seconds) within which the close entry point must complete or else be terminated. Default is 60 seconds.The CloseTimeout attribute value can be overridden.

ComputeStats

An attribute that indicates whether or not VCS is to keep track of monitor statistics for a given resource. A value of 1 indicates VCS is to keep track of the monitor time for the resource. A value of 0 indicates that VCS is not keep track of monitor statistics for a resource. See MonitorStatsParam. The default is 0.

ConfInterval

Specifies an interval in seconds. When a resource has remained online for the designated interval (all monitor invocations during the interval reported ONLINE), any earlier faults or restart attempts of that resource are ignored. This attribute is used with ToleranceLimit to allow the monitor entry point to report OFFLINE several times before the resource is declared FAULTED. If monitor reports OFFLINE more often than the number set in ToleranceLimit, the resource is declared FAULTED. However, if the resource remains online for the interval designated in ConfInterval, any earlier reports of OFFLINE are not counted against ToleranceLimit.

The agent framework uses the values of MonitorInterval (MI), MonitorTimeout (MT), and ToleranceLimit (TL) to determine how low to set the value of ConfInterval. The agent framework ensures that ConfInterval (CI) cannot be less than that expressed by the following relationship:

(MI + MT) * TL + MI + 10

Lesser specified values of ConfInterval are ignored. For example, assume that the values are 60 for MI, 60 for MT, and 0 for TL. If you specify any value lower than 70 for CI, the agent framework ignores the specified value and sets the value to 70. However, you can successfully specify and set CI to any value over 70.

ConfInterval is also used with RestartLimit to prevent VCS from restarting the resource indefinitely. VCS attempts to restart the resource on the same system according to the number set in RestartLimit within ConfInterval before giving up and failing over. However, if the resource remains online for the interval designated in ConfInterval, earlier attempts to restart are not counted against RestartLimit. Default is 600 seconds. The ConfInterval attribute value can be overridden.

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Product: Cluster Server Guides  
Manual: Cluster Server 4.1 Agent Developer's Guide  
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