iCall - test

Introduced : BIG-IP_v11.3.0
The iCall module contains interfaces permitting you to work with the iCall feature. Different places in the system are able to notify the iCall engine of events that happen on the system. Events come with contextual information describing the objects that are changing state and other details relevant to the event. You can define handlers that register interest in particular sets of events and that filter on context details associated with the incoming events. For example, you might define an event that triggers when a certain iStats value, like the number of connections on a particular virtual address, exceeds a given threshold. The contexts on the event would give information about the name of the virtual address, as well as the threshold that was exceeded. Then, a handler interested in events meeting that description would be triggered, launching a Tcl script to perform additional actions (e.g. adding a new pool member).

Interfaces

Interface Description
PeriodicHandler The PeriodicHandler interface allows you to create or delete periodic handlers. These handlers do not subscribe to events. Rather, they have three parameters: a start and end time, and an interval in seconds. The script attached to the handler will be run on the interval between the start and end times.
PerpetualHandler The PerpetualHandler interface allows you to create or delete perpetual handlers. These handlers contain a set of objects called subscriptions; a subscription registers interest in an event of a certain name. Each subscription also may optionally include a list of filters to further reduce the set of events that come in. For example, if a subscription exists to an event indicating that a pool member goes down, then the filters might be set up to restrict interest to pool members in a certain subnet. When a perpetual handler is created a Tcl script is started. It will receive and be able to handle any events that match at least one of the handler&aposs subscriptions. Perpetual handlers have an advantage over triggered handlers (see the TriggeredHandler interface) in that they can save state. However, more than one event may be handled in parallel by a triggered handler at the same time.
Script The Script interface allows you to create or delete Tcl scripts to attach to handlers.
TriggeredHandler The TriggeredHandler interface allows you to create or delete event-triggered handlers. These handlers contain a set of objects called subscriptions; a subscription registers interest in an event of a certain name. Each subscription also may optionally include a list of filters to further reduce the set of events that come in. For example, if a subscription exists to an event indicating that a pool member goes down, then the filters might be set up to restrict interest to pool members in a certain subnet. Triggered handlers do not keep state between instances of their scripts running. If you would like state to be saved, see the PerpetualHandler interface.

Structures

Structure

Description

PeriodicHandlerExpiry

A structure that contains the expiration time for a periodic handler.


Enumerations

Enumeration Description
GeneralHandlerState The state of a triggered or periodic handler.
MatchAlgorithm A list of possible match algorithms. As events come in to the system, you are able to declare a subset of events in which you are interested. These events come with a set of key-value pairs called contexts giving details relevant to the event, and handler definitions allow you to filter to a subset of these contexts. Different filtering options are possible. You can require that a particular context have an exact string value, for instance, or you can check it against a particular regular expression.
PerpetualHandlerState The state of a perpetual event handler.

Exceptions

Exception Description

Constants

Constant Type Value Description

Aliases

Alias Type Description
GeneralHandlerStateSequence GeneralHandlerState [] A sequence of handler states.
MatchAlgorithmSequence MatchAlgorithm [] A sequence of match algorithms.
MatchAlgorithmSequenceSequence MatchAlgorithm [] [] A sequence of sequences of match algorithms.
MatchAlgorithmSequenceSequenceSequence MatchAlgorithm [] [] [] A sequence of sequences of sequences of match algorithms.
PeriodicHandlerExpirySequence PeriodicHandlerExpiry [] A sequence of periodic handler expiries.
PerpetualHandlerStateSequence PerpetualHandlerState [] A sequence of handler states.

See Also

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