Checks¶

A check is one of the foundational building blocks of the monitoring system. The check determines the parts or pieces of the entity that you want to monitor, the monitoring frequency, how many monitoring zones are originating the check, and so on. When you create a new check in the monitoring system, you specify the following information:

• A name for the check
• The check’s parent entity
• The type of check you’re creating
• Details of the check
• The monitoring zones that will launch the check

The check, as created, will not trigger alert messages until you create an alarm to generate notifications, to enable the creation of a single alarm that acts upon multiple checks (e.g. alert if any of ten different servers stops responding) or multiple alarms off of a single check. (e.g. ensure both that a HTTPS server is responding and that it has a valid certificate).

$params = array(
    'type'   => 'remote.http',
    'details' => array(
        'url'    => 'http://example.com',
        'method' => 'GET'
    ),
    'monitoring_zones_poll' => array('mzlon'),
    'period' => '100',
    'timeout' => '30',
    'target_alias' => 'default',
    'label'  => 'Website check 1'
);

$response = $entity->testNewCheckParams($params);

echo $response->timestamp; // When was it executed?
echo $response->available; // Was it available?
echo $response->status;    // Status code

$entity->createCheck($params);

// Set arg to TRUE for debug information
$response = $check->test(true);

echo $response->debug_info;

$checks = $entity->getChecks();

foreach ($checks as $check) {
    echo $check->getId();
}

$check->update(array('period' => 500));

$check->delete();

Check types¶

Each check within the Rackspace Cloud Monitoring has a designated check type. The check type instructs the monitoring system how to check the monitored resource. Note: Users cannot create, update or delete check types.

Check types for commonly encountered web protocols, such as HTTP (remote.http), IMAP (remote.imap-banner) , SMTP (remote.stmp), and DNS (remote.dns) are provided. Monitoring commonly encountered infrastructure servers like MySQL (remote.mysql-banner) and PostgreSQL (remote.postgresql-banner) are also available. Monitoring custom server uptime can be accomplished with the remote.tcp banner check to check for a protocol-defined banner at the beginning of a connection. Gathering metrics from server software to create alerts against can be accomplished using the remote.http check type and the ‘extract’ attribute to define the format.

In addition to the standard Cloud Monitoring check types, you can also use agent check types if the Monitoring Agent is installed on the server you are monitoring. For a list of available check types, see the official API documentation.

Checks generate metrics that alarms will alert based upon. The metrics generated often times depend on the check’s parameters. For example, using the ‘extract’ attribute on the remote.http check, however the default metrics will always be present. To determine the exact metrics available, the Test Check API is provided.

/** @var \OpenCloud\CloudMonitoring\Resource\CheckType */
$checkType = $check->getCheckType();

$checkTypes = $service->getCheckTypes();

foreach ($checkTypes as $checkType) {
   echo $checkType->getId();
}

$checkTypeId = 'remote.dns';
$checkType = $service->getCheckType($checkTypeId);