Hyper-V VM Checkpoints Test

A checkpoint saves the state of each virtual hard disk that is attached to a virtual machine and all of the hard disk's contents, including application data files. For virtual machines on Hyper-V, a checkpoint also saves the hardware configuration information. By creating checkpoints for a virtual machine, you can restore the virtual machine to a previous state.

A typical use of checkpoints is to create a temporary backup before you update the operating system or an application, or make a configuration change on the virtual machine. A checkpoint allows you to restore the virtual machine to its previous state if the operation fails or adversely affects the virtual machine. For virtual machines on Hyper-V, checkpoints are also useful in a test environment where you want to use multiple hardware configurations on a virtual machine.

You can create multiple checkpoints for a virtual machine. However, checkpoints use hard disk space and, when allowed to proliferate, they can affect the performance of a virtual machine when it is running and during such virtual machine operations as migrating a virtual machine or storing it to the library.

To make sure that checkpoints do not affect VM performance, administrators need to continuously track checkpoint growth per VM, identify ‘heavy-weight’ and obsolete checkpoints that may not be of use any longer, and purge them. The Hyper-V VM Checkpoints test helps administrators achieve the same. This test reports the count of large and aged checkpoints per VM, and reveals the names of thesecheckpoints, so that administrators can decide whether/not these checkpoints can be removed to make more storage space available for the VM.

Note:

This test will report metrics for Microsoft Hyper-V Server 2012 only.

Target of the test : A Hyper-V / Hyper-V VDI server

Agent executing the test : An internal agent

Output of the test : One set of results for each VM on a Hyper-V host monitored

Configurable parameters for the test
  1. Test period - How often should the test be executed
  2. Host - The host for which the test is to be configured.
  3. port - The port number at which the configured HOST listens.
  4. age limit in days - By default, the value of this parameter is set to 15 days. This implies that the test will report all those snapshots that are more than 15 days old as Aged snapshots. If required, you can change the age limit.
  5. size limit in mb - By default, the value of this parameter is set to 10000 MB. This implies that the test will report all those snapshots that have a size more than 10000 MB as Large snapshots. If required, you can change this limit.
  6. domain, admin user, admin password, and confirm password – By default, this test connects to each virtual guest remotely and attempts to collect “inside view” metrics. Accordingly, the inside view using flag is set to Remote connection to VM (Windows) by default. To obtain a remote connection, the test must be configured with the privileges of an administrative user to the domain within which the guests reside. The first step towards this is to specify the DOMAIN within which the virtual guests reside. The admin user and admin password will change according to the domain specification. Discussed below are the different values that the domain parameter can take, and how they impact the admin user and admin password specifications:

    • If the VMs belong to a single domain:  If the guests belong to a specific domain, then specify the name of that domain against the domain parameter. In this case, any administrative user in that domain will have remote access to all the virtual guests. Therefore, an administrator account in the given domain can be provided in the ADMIN USER field and the corresponding password in the ADMIN PASSWORD field. Confirm the password by retyping it in the CONFIRM PASSWORD text box.
    • If the VMs belong to different domains: In this case, you might want to provide multiple domain names. If this is done, then, to access the guests in every configured domain, the test should be configured with the required user privileges; this implies that along with multiple DOMAIN names, multiple ADMIN USER names and ADMIN PASSWORDs would also have to be provided. To help administrators provide these user details quickly and easily, the eG administrative interface embeds a special configuration page. To access this page, simply click on the encircled '+' icon that appears alongside the admin user parameter of this test in the test configuration page. To know how to use the special page, refer to Configuring Users for VM Monitoring of this document.
    • If the inside view using flag is set to ‘eG VM Agent (Windows)’: On the other hand, if the inside view using flag is set to eG VM Agent (Windows) , then it implies that the inside view can be obtained without domain administrator privileges. Therefore, set the domain, admin user, and admin password parameters to none.

  7. dd frequency - To make diagnosis more efficient and accurate, the eG Enterprise suite embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test
  8. DETAILED DIAGNOSIS - To make diagnosis more efficient and accurate, the eG Enterprise suite embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

    The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

    • The eG manager license should allow the detailed diagnosis capability
    • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements reported by the test
Measurement Description Measurement Unit Interpretation

Number of checkpoints

Indicates the number of checkpoints for this VM.

Number

 

Aged checkpoints count

Indicates the number of checkpoints of this VM, the age of which is more than the age limit configured for this test.

Number

Use the detailed diagnosis of this measure to identify the aged checkpoints.

Large checkpoints count

Indicates the number of checkpoints of this VM that are of a size greater than the size limit configured for this test.

Number

Use the detailed diagnosis of this measure to identify the large-sized checkpoints.