Composite Tests

Composite performance metrics allow you to create unique tests by selecting two or more existing tests from the same or multiple network devices and specifying a mathematical formula to calculate the final test result.

Composite tests are similar to pre-existing (or traditional) tests where you specify warning/critical thresholds, test intervals, units, action profiles, and schedules The underlying tests that comprise a composite test automatically inherit test intervals and schedules from the composite test to ensure validity of the result for the composite test (depending on the formula you specify). Because of this, you can only assign a regular test to a single (one) composite test. Also, you cannot change the polling interval of the regular tests while they are assigned to a composite test.

The pre-existing tests retain their own thresholds, action profiles, and so on. This allows you to trigger actions for both composite and pre-existing tests independently.

The formula you configure references the pre-existing tests using the alias of T1, T2 and so on. You can also use operators such as +, - , *, / , and ( ) for grouping. For example:

( (T1 * 5) + (T2 + 10) ) / T3

You cannot delete a pre-existing test that is part of a composite test. On individual test update pages, the option to delete the test and inherited parameters is disabled. In Administration > Devices > Tests, attempting to update thresholds, action profiles, and inherited parameters causes a list of skipped tests to display, and Traverse discards the update to tests that are part of a composite test.

Supported Operations

Operator	Description	Example
+ - * /	Addition, subtraction, multiplication, division	(T1 * 5) + (T2 - 3)
m % n	remainder when dividing m by n	T1 % 10
pow	raise the preceding number to the power of the following number	2 pow 32 - 1
int	round the following number to an integer	int T1
cond ? t : f	If condition is true, then return value t else return value f	T1 > 20 ? T2 : T3
<, >, ==	Comparison Operators: less than. greater than, equals	T1 < 10
<=, =>	Comparisons: less than or equal, greater than or equal	T1 >= 100
<> , !=	Comparison: not equal	T1 <> T2
&&, \|\|	Boolean: AND, OR	(T1 > 10) \|\| (T2 < 5)

Comparison and boolean operations yield 1 for true, and 0 for false if used as numbers. Expressions are evaluated using the precedence rules found in Java, and parenthesis can be used to control the evaluation order.

Creating Composite Tests

Navigate to Administration > Devices.
On the Manage Devices page, find the device for which you want to create a test and click Tests.
On the Manage Tests page, click Create New Advanced Tests and scroll down to the Composite Tests section, and select the check box to create a new composite test.
Enter the test name, test interval, warning and critical thresholds, and an action profile (optional). Note that you can also do this after selecting the child tests.
Click the Add link that is displayed next to the Child Tests field. Pre-existing Test Selection pane is displayed, showing available tests for the given device. You can scroll through and select one or more tests for the given device.
To select tests from other devices, click the Search tab, specify a search criteria for the device, and click the Add button at the bottom of the panel. For example, if you select Device Name, then enter *, then all tests created for all device names will be listed on the Results tab.
Click the Search button to retrieve all the devices (and available tests) for the specified criteria.
Click the Results tab and select the tests you want to add and click Add Tests.
Traverse automatically assigns aliases (T1, T2, and so on) to the tests you add to the composite test.
In the Expression field, enter a composite test formula. For example, if you added two tests, you can enter:

T1 + T2

Click Provision Tests.
The composite test display in the Status > Test page and Manage Tests pages.