Apmec Monitoring Framework¶

Introduction¶

Apmec monitoring framework provides the MEM operators and MEA vendors to write a pluggable driver that monitors the various status conditions of the MEA entities it deploys and manages.

How to write a new monitor driver¶

A monitor driver for apmec is a python module which contains a class that inherits from “apmec.mem.monitor_drivers.abstract_driver.MEAMonitorAbstractDriver”. If the driver depends/imports more than one module, then create a new python package under apmec/mem/monitor_drivers folder. After this we have to mention our driver path in setup.cfg file in root directory.

For example:

apmec.apmec.monitor_drivers =
    ping = apmec.mem.monitor_drivers.ping.ping:MEAMonitorPing

Following methods need to be overridden in the new driver:

def get_type(self)

This method must return the type of driver. ex: ping

def get_name(self)

This method must return the symbolic name of the mea monitor plugin.

def get_description(self)

This method must return the description for the monitor driver.

def monitor_get_config(self, plugin, context, mea)

This method must return dictionary of configuration data for the monitor driver.

def monitor_url(self, plugin, context, mea)

This method must return the url of mea to monitor.

def monitor_call(self, mea, kwargs)

This method must either return boolean value ‘True’, if MEA is healthy. Otherwise it should return an event string like ‘failure’ or ‘calls-capacity-reached’ based on specific MEA health condition. More details on these event is given in below section.

Custom events¶

As mentioned in above section, if the return value of monitor_call method is other than boolean value ‘True’, then we have to map those event to the corresponding action as described below.

For example:

vdu1:
  monitoring_policy:
    ping:
      actions:
        failure: respawn

In this example, we have an event called ‘failure’. So whenever monitor_call returns ‘failure’ apmec will respawn the MEA.

Actions¶

The available actions that a monitor driver can call when a particular event occurs.

1. respawn
2. log

How to write TOSCA template to monitor MEA entities¶

In the vdus section, under vdu you can specify the monitors details with corresponding actions and parameters.The syntax for writing monitor policy is as follows:

vduN:
  monitoring_policy:
    <monitoring-driver-name>:
      monitoring_params:
        <param-name>: <param-value>
        ...
      actions:
        <event>: <action-name>
        ...
    ...

Example Template¶

vdu1:
  monitoring_policy:
    ping:
      actions:
        failure: respawn

vdu2:
  monitoring_policy:
    http-ping:
      monitoring_params:
        port: 8080
        url: ping.cgi
      actions:
        failure: respawn

  acme_scaling_driver:
    monitoring_params:
      resource: cpu
      threshold: 10000
    actions:
      max_foo_reached: scale_up
      min_foo_reached: scale_down