Product Documentation

Connector configurations

The first time you use the App Layering service, you need to add at least one connector configuration to use for creating layers and publishing layered images.

A connector is an interface that gives the App Layering appliance access to your hypervisor or provisioning service for the purpose of creating layers or publishing layered images.

A connector configuration is a stored set of values for the App Layering appliance to use when connecting to a storage location in your hypervisor or provisioning service. Each connector configuration includes a storage location, credentials for authentication, and any other information required for the appliance to interface with the environment where you are creating layers and publishing layered images.

Why use connector configurations

Connector configurations allow the App Layering appliance to access locations in your environment for creating layers or publishing layered images. This automates and speeds up the file transfers involved in these processes.

You can use a connector configuration:

  • For importing an OS image when creating a new OS layer.
  • For creating App and Platform layers, and new versions of your OS layer. A connector configuration can also run a script that you specify in the Script Path field.
  • For publishing layered images to your hypervisor or provisioning service. A connector configuration can also run a script that you specify in the Script Path field, for example, the first time that the image is started.

Importing your OS image into an OS layer

When you create an OS layer, you need a connector configuration to give the appliance access to the location of the OS image.

Hyper-V:

The Hyper-V connector configuration does not support OS import. Instead, you manually copy the prepared OS to the appliance’s File Share for import into the OS layer.

Creating layers

To speed up layer creation, you need a connector configuration with the credentials for the hypervisor location where you plan to install the software for a layer. This connector configuration includes a Packaging Cache option, which is enabled by default to afford you the best layering performance.

Publishing layered images

You need a connector configuration for each location to which you are publishing layered images. Once published, you use layered images to provision systems for specific groups of users.

Requirements

To create a connector configuration, you need to meet the following requirements.

Credentials

Valid account credentials that the appliance can use to access a location in your environment. For details about the values you need, select the hypervisor or provisioning service later in this section.

Disk space for cache

(Applies to all hypervisors, except for Azure) By default, the Packaging cache size is set to the recommended starting level for your hypervisor, and you should allow enough disk space so that you can increase the cache size, if needed. For details, see the next section.

About packaging cache size and hit rate

Connector configurations for all hypervisors except Azure let you configure space for a Packaging cache. The appliance uses this cache on your hypervisor to speed up layer packaging.

Packaging cache size

Using Packaging cache is highly recommended, so by default, the Packaging cache size is set to a recommended starting size for your hypervisor:

  • vSphere: 250GB
  • XenServer: 480GB
  • Hyper-V: 200GB
  • Nutanix: 480GB

As more unique App layers are created, you may need to increase the Packaging cache size. In general, the more App layers, the bigger the cache should be.

Hit rate

The hit rate is the percentage of times the appliance has found a disk in the cache. A low hit rate means the cache is not offering much benefit, because there is not enough space for the number of disks you have.

If you have a low hit rate, you should improve it by increasing the Packaging cache size, as described below. Increasing the cache size allows more disks to be stored in the cache. It also increases the likelihood of finding a disk needed for packaging in the cache. This results in a higher hit rate.

View connector configurations

The System > Configuration tab lists the connector configurations that you have created.

Image of the Connectors tab

Sort connector configurations

By default, connector configurations are listed in alphabetical order by name. You can also sort them by platform.

View connector configuration details

When caching is enabled for a connector configuration, the Connectors tab displays the cache size for that configuration.

Image of the cache size option

To see the values for any given connector configuration:

  1. Click the info icon to the left of the name. Details about the connector configuration are displayed.

View Cache size and Hit rate

The Packaging Cache Size and Hit rate are displayed when the Packaging Cache Size is set to a value greater than zero (0).

Add a connector configuration

This section explains how to add a connector configuration using the System > Connectors tab, which is where you manage your configurations.

If when creating a layer or image template you don’t find the connector configuration you need, you can also add a new one by selecting New on the wizard’s Connector tab. From there you can use the detailed steps below.

To add a connector configuration, follow these steps:

  1. Access the management console, and select System > Connectors. This is where connector configurations are listed.
  2. Click Add Connector Config in the Action bar. This opens a dialog box where you can select the type of connector configuration to create.
  3. Choose the connector type from the drop-down menu.
  4. Complete the fields on the connector configuration page.
  5. Click the Test button to verify that the connector can access the location specified using the credentials supplied.
  6. Click Save. The new connector configuration appears on the Connector tab.

Image of the connector configuration

Edit a connector configuration

To edit a connector configuration:

  1. Access the management console, and select System > Connectors.
  2. Select the connector and click Edit Connector Config on the action panel. The connector configuration is displayed.
  3. Update the configuration, as needed.
  4. Click the Test button to verify that the connector can access the location specified using the credentials supplied.
  5. Click Save. The connector configuration is updated.

Increase the Cache size and Hit rate

To improve the utility of the cache and therefore increase the hit rate by editing the Packaging Cache Size:

  1. Select the connector and click Edit Connector Config on the action panel.
  2. Scroll to Layer Disk Cache Size in GB and enter the amount of space that the cache can occupy.
  3. Click the Test button to verify that the connector can access the location specified by using the credentials supplied.
  4. Click Save. The connector configuration is updated.

Continue adjusting the cache size until you achieve the layering performance you are looking for.

Disable or re-enable caching

Caching is now enabled and set to a recommended starting size by default, and we strongly recommend that you use it. If you decide to disable caching for a connector configuration, set the cache size to zero (0). If you need to re-enable it, simply increase the Packaging cache size.

Delete a connector configuration

If a connector configuration is deleted by another user while you are working in the Connectors tab, it may take a few minutes for the connector configuration to disappear from the list.

To delete a connector configuration:

  1. In the management console, select System > Connectors.
  2. Make sure that the connector configuration is not in use.
  3. Click Delete Connector Config on the Action bar.
  4. In the pop-up window that opens, select Yes. The connector configuration is deleted.

Messages you may receive when deleting configurations

If a connector configuration is in use when you attempt to delete it, you receive a message similar to the following example.

Example:

Validation Error: Unable to delete connector configuration ‘Citrix PVS - ConnectorExample’ as it is in use. If you receive this error message, remove the connector configuration from the layer or image template where it is still in use. Then delete the configuration.