Ice Docs

IceBox Administration

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An IceBox server internally creates an object called the service manager that is responsible for loading and initializing the configured services. You can optionally expose this object to remote clients, such as the IceBox and IceGrid administrative utilities, so that they can execute certain administrative tasks.

The Slice definitions shown below comprise the IceBox administrative interface:

Slice
module IceBox
{
    exception AlreadyStartedException {}
    exception AlreadyStoppedException {}
    exception NoSuchServiceException {}


    interface ServiceObserver
    {
        void servicesStarted(Ice::StringSeq services);
        void servicesStopped(Ice::StringSeq services);
    }


    interface ServiceManager
    {
        void startService(string service)
            throws AlreadyStartedException, NoSuchServiceException;


        void stopService(string service)
            throws AlreadyStoppedException, NoSuchServiceException;


        bool isServiceRunning(string service)
            throws NoSuchServiceException;


        void addObserver(ServiceObserver* observer);


        void shutdown();
    }
}

The ServiceManager interface provides access to the service manager object of an IceBox server. It defines the following operations:

  • startService Starts a pre-configured service that is currently inactive. This operation cannot be used to add new services at run time, nor will it cause an inactive service's implementation to be reloaded. If no matching service is found, the operation throws NoSuchServiceException. If the service is already active, the operation throws AlreadyStartedException.
  • stopService Stops an active service but does not unload its implementation. The operation throws NoSuchServiceException if no matching service is found, and AlreadyStoppedException if the service is stopped at the time stopService is invoked.
  • isServiceRunning Returns true if the service is running, and false otherwise. The operation throws NoSuchServiceException if no matching service is found.
  • addObserver Adds an observer that is called when IceBox services are started or stopped. The service manager ignores operations that supply a null proxy, or a proxy that has already been registered.
  • shutdown Terminates the services and shuts down the IceBox server.

An administrative client that is interested in receiving callbacks when IceBox services are started or stopped must implement the ServiceObserver interface and register the callback object's proxy with the service manager using its addObserver operation. The ServiceObserver interface defines two operations:

  • servicesStarted IceBox invokes this operation upon registration if at least one service is running, passing the names of the running services. It invokes the operation again after each successful service start.
  • servicesStopped IceBox invokes this operation with the names of services it successfully stops, including during server shutdown.

The IceBox server unregisters an observer if the invocation of either operation causes an exception.

Our discussion of IceGrid includes an example that demonstrates how to register a ServiceObserver callback with an IceBox server deployed with IceGrid.

IceBox's administrative functionality is disabled by default. You can enable it using the Ice administrative facility by defining endpoints for the Ice.Admin object adapter with the property Ice.Admin.Endpoints.

With the administrative facility enabled, IceBox registers an administrative facet with the name IceBox.ServiceManager. We discuss the identity of the admin object below.

When you enable the service manager, IceBox adds it as a facet of the server's admin object. As a result, the identity of the service manager is the same as that of the admin object, and the name of its facet is IceBox.ServiceManager.

The identity of the admin object uses either a UUID or a statically-configured value for its category, and the value admin for its name. For example, consider the following property definitions:

Properties
Ice.Admin.Endpoints=tcp -h 127.0.0.1 -p 10001
Ice.Admin.InstanceName=IceBox

In this case, the identity of the admin object is IceBox/admin.

When administration is enabled in the IceBox server, IceBox adds the built-in facets of each service communicator, except Process, to the server's admin object under these names:

  • IceBox.Service.service-name.facet-name for a service with its own communicator, for example IceBox.Service.Greeter.Properties.
  • IceBox.SharedCommunicator.facet-name for the shared communicator, for example IceBox.SharedCommunicator.Properties.

To add only some of these facets, list their names in the IceBox server's Ice.Admin.Facets property. This property filters every facet of the admin object, including IceBox.ServiceManager, so list every facet you use:

Properties
Ice.Admin.Facets=IceBox.ServiceManager IceBox.Service.Greeter.Properties

To keep a service's facets out of the admin object, set Ice.Admin.Enabled to 0 in that service's configuration. The shared communicator uses a merged configuration, so this setting applies to all services that share it.

A client requiring administrative access to the service manager must first obtain (or be able to construct) a proxy for the admin object. The default identity of the admin object uses a UUID for its category, which means the client cannot predict the identity and therefore will be unable to construct the proxy itself. If the IceBox server is deployed with IceGrid, the client can use the technique described in our discussion of IceGrid to access its admin object.

In the absence of IceGrid, the IceBox server should set the Ice.Admin.InstanceName property if remote administration is required. In so doing, the identity of the admin object becomes well-known, and a client can construct the proxy on its own. For example, let's assume that the IceBox server defines the following property:

Properties
Ice.Admin.InstanceName=IceBox

A client can define the proxy for the admin object in a configuration property as follows:

Properties
ServiceManager.Proxy=IceBox/admin -f IceBox.ServiceManager:tcp -h 127.0.0.1 -p 10001

The proxy option -f IceBox.ServiceManager specifies the name of the service manager's administrative facet.

IceBox includes C++ and Java implementations of an administrative utility. The utilities have the same usage:

Usage: iceboxadmin [options] [command...]
Options:
-h, --help           Show this message.
-v, --version        Display the Ice version.


Commands:
status SERVICE       Get the status of a service.
start SERVICE        Start a service.
stop SERVICE         Stop a service.
shutdown             Shutdown the server.

The C++ utility is named iceboxadmin. The Java utility is represented by the class com.zeroc.IceBox.Admin.

The status command invokes isServiceRunning and prints running or stopped.

The start command is equivalent to invoking startService on the service manager interface. Its purpose is to start a pre-configured service; it cannot be used to add new services at run time. Note that this command does not cause the service's implementation to be reloaded.

Similarly, the stop command stops the requested service but does not cause the IceBox server to unload the service's implementation.

The shutdown command stops all active services and shuts down the IceBox server.

The C++ and Java utilities obtain the service manager's proxy from the property IceBoxAdmin.ServiceManager.Proxy, therefore this proxy must be defined in the program's configuration file or on the command line, and the proxy's contents depend on the server's configuration. If the IceBox server is deployed with IceGrid, we recommend using the IceGrid administrative utilities instead, which provide equivalent commands for administering an IceBox server. Otherwise, the proxy should have the endpoints and identity configured for the server.

For an IceBox server configured with Ice.Admin.Endpoints=tcp -h 127.0.0.1 -p 10001 and Ice.Admin.InstanceName=IceBox, save the following property in admin.cfg:

Properties
IceBoxAdmin.ServiceManager.Proxy=IceBox/admin -f IceBox.ServiceManager:tcp -h 127.0.0.1 -p 10001

Query the status of the Greeter service:

Shell
iceboxadmin --Ice.Config=admin.cfg status Greeter