Resource Monitoring¶

Monitoring Type¶

Blazar supports 2 types of monitoring - push-based and polling-based.

1. Push-based monitoring

   The monitor listens to notification messages sent by other components, e.g., sent by Nova for the host monitoring plugin. And it picks up messages which refer to the resources managed by Blazar. Event types, topics to subscribe and notification callbacks are provided by monitoring plugins.

2. Polling-based monitoring

   The blazar-manager periodically calls a states check method of monitoring plugins. Then, the monitoring plugins check states of resources, e.g., List Hypervisors of the Compute API is used for the host monitoring plugin.

Admins can enable/disable these monitoring by setting configuration options.

Healing¶

When the monitor detects a resource failure, it heals reservations which are expected to suffer from the failure.

Flags¶

Leases and reservations have flags that indicate states of reserved resources. Reservations have the following two flags:

• missing_resources: If any resource allocated to the reservation fails and no alternative resource found, this flag is set True.
• resources_changed: If any resource allocated to the active reservation and alternative resource is reallocated, this flag is set True.

Leases have the following flag:

• degraded: If the missing_resources or the resources_changed flags of any reservation included in the lease is True, then it is True.

Lease owners can see health of the lease and reservations included in the lease by checking these flags.

Monitoring Resources¶

Resource specific functionality is provided as a monitoring plugin. The following resource is currently supported.