os-faults 0.2.7

Example 1. DevStack

Connection to DevStack can be specified using the following YAML file:

cloud_management:
  driver: devstack
  args:
    address: devstack.local
    auth:
      username: stack
      private_key_file: cloud_key
    iface: enp0s8

OS-Faults library will connect to DevStack by address devstack.local with user stack and SSH key located in file cloud_key. Default networking interface is specified with parameter iface. Note that user should have sudo permissions (by default DevStack user has them).

DevStack driver is responsible for service discovery. For more details please refer to driver documentation: http://os-faults.readthedocs.io/en/latest/drivers.html#devstack-systemd-devstackmanagement

Example 2. An OpenStack with services, containers and power management

An arbitrary OpenStack can be handled too with help of universal driver. In this example os-faults is used as Python library.

cloud_config = {
    'cloud_management': {
        'driver': 'universal',
    },
    'node_discover': {
        'driver': 'node_list',
        'args': [
            {
                'ip': '192.168.5.127',
                'auth': {
                    'username': 'root',
                    'private_key_file': 'openstack_key',
                }
            },
            {
                'ip': '192.168.5.128',
                'auth': {
                    'username': 'root',
                    'private_key_file': 'openstack_key',
                }
            }
        ]
    },
    'services': {
        'memcached': {
            'driver': 'system_service',
            'args': {
                'service_name': 'memcached',
                'grep': 'memcached',
            }
        }
    },
    'containers': {
        'neutron_api': {
            'driver': 'docker_container',
            'args': {
                'container_name': 'neutron_api',
            }
        }
    },
    'power_managements': [
        {
            'driver': 'libvirt',
            'args': {
                'connection_uri': 'qemu+unix:///system',
            }
        },
    ]
}

The config contains all OpenStack nodes with credentials and all services/containers. OS-Faults will automatically figure out the mapping between services/containers and nodes. Power management configuration is flexible and supports mixed bare-metal / virtualized deployments.

First let’s establish a connection to the cloud and verify it:

cloud_management = os_faults.connect(cloud_config)
cloud_management.verify()

The library can also read configuration from a file in YAML or JSON format. The configuration file can be specified in the OS_FAULTS_CONFIG environment variable. By default the library searches for file os-faults.{json,yaml,yml} in one of locations:

• current directory

• ~/.config/os-faults

• /etc/openstack

Now let’s make some destructive action:

cloud_management.get_service(name='memcached').kill()
cloud_management.get_container(name='neutron_api').restart()

1. Service actions

Get a service and restart it:

cloud_management = os_faults.connect(cloud_config)
service = cloud_management.get_service(name='glance-api')
service.restart()

Available actions:

• start - start Service

• terminate - terminate Service gracefully

• restart - restart Service

• kill - terminate Service abruptly

• unplug - unplug Service out of network

• plug - plug Service into network

2. Container actions

Get a container and restart it:

cloud_management = os_faults.connect(cloud_config)
container = cloud_management.get_container(name='neutron_api')
container.restart()

Available actions:

• start - start Container

• terminate - terminate Container gracefully

• restart - restart Container

3. Node actions

Get all nodes in the cloud and reboot them:

nodes = cloud_management.get_nodes()
nodes.reboot()

Available actions:

• reboot - reboot all nodes gracefully

• poweroff - power off all nodes abruptly

• reset - reset (cold restart) all nodes

• disconnect - disable network with the specified name on all nodes

• connect - enable network with the specified name on all nodes

4. Operate with nodes

Get all nodes where a service runs, pick one of them and reset:

nodes = service.get_nodes()
one = nodes.pick()
one.reset()

Get nodes where l3-agent runs and disable the management network on them:

fqdns = neutron.l3_agent_list_hosting_router(router_id)
nodes = cloud_management.get_nodes(fqdns=fqdns)
nodes.disconnect(network_name='management')

5. Operate with services

Restart a service on a single node:

service = cloud_management.get_service(name='keystone')
nodes = service.get_nodes().pick()
service.restart(nodes)

6. Operate with containers

Terminate a container on a random node:

container = cloud_management.get_container(name='neutron_ovs_agent')
nodes = container.get_nodes().pick()
container.restart(nodes)