Freezing a service

When preparing for a temporary maintenance shutdown, you may want to freeze a service without releasing the resource. When a service is frozen, you prevent resources from being reassigned. The resource request is adjusted to suit resources allocated currently, so that the service neither receives more resources from EGO nor releases resources to EGO.

Before you begin

  • You must be a cluster administrator or have the Services Control permission to freeze a service.
  • The service must be registered and in the STARTED or ALLOCATING state.

About this task

While you can usually freeze a service from the cluster management console, you may need to freeze a service manually from the command line if you stopped the WEBGUI service or you cannot access the console.

When you freeze a large number of system service instances, tune performance with the EGO_MAX_CHUNK_SIZE parameter, which specifies the number of requests EGO handles in chunks, in the $EGO_CONFDIR/ego.conf file.

Procedure

  • Follow these steps to freeze a service from the cluster management console:
    1. From the cluster management console Dashboard, select System & Services > EGO Services > System Services.

      The Services page displays.

    2. In your consumer tree, navigate to where the service you want to freeze is registered, or click the cluster name to see a list of all registered services.
    3. For the service you want to freeze, click Actions and select Freeze.
    4. Click OK to confirm that you want to freeze the service.
  • Follow these steps to freeze a service manually from the command line:
    1. Run egosh service view to see the current status of your services.

      If the service you want to freeze is in STARTED or ALLOCATING state, proceed to the next step.

    2. Run egosh service freeze service_name where service_name is the name of the service you want to freeze.

Results

Your service is placed in the FROZEN state.

What to do next

After a service is FROZEN, you can stop or unfreeze the service. You cannot, however, migrate the service.
  • If you stop the service, all resources allocated to the service are released and the corresponding service instances are killed. The service is then placed in the DEFINED state.
  • If you unfreeze the service, the service is enabled to receive more resources or release resources as required. It is then placed in the STARTED or ALLOCATING state based on the number of service instances in the RUN and HOLD states.