Eucalyptus provides access to the current view of service state and the ability to manipulate the state. You can inspect the service state to either ensure system health or to identify faulty services. You can modify a service state to maintain activities and apply external service placement policies.
View Service State
Use the euserv-describe-services command to view the service state. The output indicates:
- Component type of the service
- Partition in which the service is registered
- Unique name of the service
- Current view of service state
- Last reported epoch (this can be safely ignored)
- Service URI
- Fully qualified name of the service (This is needed for manipulating services that did not get unique names during registration. For example: internal services like DNS)
The default output includes the services that are registered during configuration, as well as information about the DNS service, if present. You can obtain additional service state information, such as internal services, by providing the
-aflag.
You can also make requests to retrieve service information that is filtered by either:
- current state (for example, )
- host where service is registered
- partition where service is registered
- type of service (for example, CC or Walrus)
When you investigate service failures, you can specify
-eventsto return a summary of the last fault. You can retrieve extended information (primarily useful for debugging) by specifying-events -events-verbose.
Heartbeat Service
http://CLCIPADDRESS:8773/services/Heartbeat provides a list of components and their respective statuses. This allows you to find out if a service is enabled without requiring cloud credentials.
Modify Service State
To modify a service:
Enter the following command on the CLC, Walrus, or SC machines:
systemctl stop eucalyptus-cloud.service
On the CC, use the following command:
systemctl stop eucalyptus-cluster.service
If you want to shut down the SC for maintenance. The SC is SC00 is ENABLED and needs to be DISABLED for maintenance.
To stop SC00 first verify that no volumes or snapshots are being created and that no volumes are being attached or detached, and then enter the following command on SC00:
systemctl stop eucalyptus-cloud.service
To check status of services, you would enter:
euserv-describe-services
When maintenance is complete, you can start the eucalyptus-cloud process on SC00 , which will enter the DISABLED state by default.
systemctl start eucalyptus-cloud.service
Monitor the state of services using euserv-describe-services until SC00 is ENABLED .