Virtual Machines - AHV Test

Live migration is supported on an AHV cluster. Live migration is the ability to move a running VM from one host (node) to another in the same cluster, without any downtime or loss of connectivity. Live migration can be initiated manually or automatically. While manual migration can be initiated via the Prism Element interface, automatic VM migration is triggered by the AHV Dynamic Resource Scheduler or the VM High Availability (VMHA) capability of an AHV cluster. The scheduler monitors each individual node's CPU and memory utilization. In the event where a node's CPU allocation breaches its threshold (currently 85% of host CPU), the scheduler automatically migrates VMs off that host to re-balance the workload. VMHA, if enabled for a cluster, ensures that critical VMs are automatically restarted on another AHV Hypervisor (AHV) host in the cluster if a host fails.

Where migration is automatic, administrators may want to keep close track of VM movement, so that they can accurately tell on which host a VM is operating at a given point in time. The Virtual Machines - AHV test provides administrators with this insight. This test indicates whether any guests have migrated to or from the virtual server, and if so, which ones are those. In addition, the test also enables administrators to determine how many guests have registered with the AHV server, and how many of these are currently running. Additionally, for VDI environments, the test reports the number and names of VMs with users logged in and the ones without any users logged in; this way, unused VMs that are unnecessarily hogging resources.

Target of the test : A Nutanix AHV server

Agent deploying the test : A remote agent

Outputs of the test : One set of results for the Nutanix AHV server monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed

Host

The host for which the test is to be configured.

Port

The port at which the specified host listens. By default, this is NULL

Is VDI Server

By default, this flag is set to No indicating that the test is being configured to execute for a Nutanix AHVmodel and not a Nutanix AHV VDI model. This distinction needs to be made, since this test reports 2 additional measures for a Nutanix AHV VDI server - namely, VMs with users and VMs without users.DD For Registered VMS.

Prism Element IP

If the eG manager had discovered the target Nutanix AHV server by connecting to the Nutanix Prism Element, then the IP address of the Nutanix Prism Element server used for discovering this Nutanix AHV server would be automatically displayed against the Prism Element IP parameter; similarly, the Prism Element User and Prism Element Password text boxes will be automatically populated with the Prism Element user credentials, using which Nutanix AHV discovery was performed.

If this Nutanix AHV server has not been discovered using the Nutanix Prism Element, but you still want to monitor the Nutanix AHV server via the Prism Element, then select the IP address of the Prism Element server that you wish to use for monitoring the Nutanix AHV server from the Prism Element IP list. By default, this list is populated with the IP address of all Nutanix Prism Element hosts that were added to the eG Enterprise system at the time of discovery. Upon selection, the Prism Element user and Prism Element Password that were pre-configured for that Nutanix Prism Element will be automatically displayed against the respective text boxes.

On the other hand, if the IP address of the Prism Element server of interest to you is not available in the list, then, you can add the details of the Prism Element server on-the-fly, by selecting the Other option from the Prism Element IP list. This will invoke the MANAGER DISCOVERY - VIRTUAL PLATFORM SETTINGS page. Refer to the Configuring eG Enterprise to Monitor Nutanix AHV topic for details on how to use this page.

Prism Element User, Prism Element Password and Confirm Password

If the eG manager had discovered the target Nutanix AHV server by connecting to the Nutanix Prism Element, then the IP address of the Nutanix Prism Element server used for discovering this Nutanix AHV server would be automatically displayed against thePrism Element IP parameter; similarly, the Prism Element User and Prism Element Password text boxes will be automatically populated with the Prism Element user credentials, using which Nutanix AHV discovery was performed.

If this Nutanix AHV server has not been discovered using the Nutanix Prism Element, but you still want to monitor the Nutanix AHV server via the Prism Element, then select the IP address of the Prism Element server that you wish to use for monitoring the Nutanix AHV server from the Prism Element IP list. By default, this list is populated with the IP address of all Nutanix Prism Element hosts that were added to the eG Enterprise system at the time of discovery. Upon selection, the Prism Element User and Prism Element Password that were pre-configured for that Prism Element server will be automatically displayed against the respective text boxes.

On the other hand, if the IP address of the Prism Element server of interest to you is not available in the list, then, you can add the details of the Prism Element server on-the-fly, by selecting the Other option from the Prism Element IP list. This will invoke the MANAGER DISCOVERY - VIRTUAL PLATFORM SETTINGS page. Refer to the Configuring eG Enterprise to Monitor Nutanix AHV topic for details on how to use this page.

SSL

By default, the Nutanix Prism Element server is SSL-enabled. Accordingly, the SSL flag is set to Yes by default. This indicates that the eG agent will communicate with the Prism Element server via HTTPS by default.

WebPort

By default, the Nutanix Prism Element server listens on port 9440. This implies that while monitoring a Nutanix AHV server via the Prism Element server, the eG agent connects to port 9440.

Exclude VMs

Administrators of some virtualized environments may not want to monitor some of their less-critical VMs - for instance, VM templates - both from 'outside' and from 'inside'. The eG agent in this case can be configured to completely exclude such VMs from its monitoring purview. To achieve this, provide a comma-separated list of VMs to be excluded from monitoring in the Exclude VMs text box. Instead of VMs, VM name patterns can also be provided here in a comma-separated list. For example, your Exclude VMs specification can be: *xp,*lin*,win*,vista. Here, the * (asterisk) is used to denote leading and trailing spaces (as the case may be). By default, this parameter is set to none indicating that the eG agent obtains the inside and outside views of all VMs on a virtual host by default. By providing a comma-separated list of VMs/VM name patterns in the Exclude VMs text box, you can make sure the eG agent stops collecting 'inside' and 'outside' view metrics for a configured set of VMs.

Ignore VMs Inside View

Administrators of some high security Hyper-V environments might not have permissions to internally monitor one/more VMs. The eG agent can be configured to not obtain the 'inside view' of such ‘inaccessible’ VMs using the Ignore VMs Inside View parameter. Against this parameter, you can provide a comma-separated list of VM names, or VM name patterns, for which the inside view need not be obtained. For instance, your Ignore VMs Inside View specification can be: *xp,*lin*,win*,vista. Here, the * (asterisk) is used to denote leading and trailing spaces (as the case may be). By default, this parameter is set to none indicating that the eG agent obtains the inside view of all VMs on a Hyper-V host by default.

Note:

While performing VM discovery, the eG agent will not discover the operating system of the VMs configured in the Ignore VMs Inside View text box.

Ignore WINNT

By default, the eG agent does not support the inside view for VMs executing on Windows NT operating systems. Accordingly, the Ignore WINNT flag is set to Yes by default.

Inside View Using

By default, this test communicates with every VM remotely and extracts “inside view” metrics. Therefore, by default, the Inside View Using flag is set to Remote connection to VM (Windows).

Typically, to establish this remote connection with Windows VMs in particular, eG Enterprise requires that the eG agent be configured with domain administrator privileges. In high-security environments, where the IT staff might have reservations about exposing the credentials of their domain administrators, this approach to extracting “inside view” metrics might not be preferred. In such environments therefore, eG Enterprise provides administrators the option to deploy a piece of software called the eG VM Agent (Windows) on every Windows VM; this VM agent allows the eG agent to collect “inside view” metrics from the Windows VMs without domain administrator rights. Refer toConfiguring the eG Agent to Collect Current Hardware Status Metrics for more details on the eG VM Agent. To ensure that the “inside view” of Windows VMs is obtained using the eG VM Agent, set theInside View Using flag to eG VM Agent (Windows). Once this is done, you can set the Domain, Admin User, and Admin Password parameters to none.

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. In order to obtain a remote connection, the test must be configured with user privileges that allow remote communication with the virtual guests. 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 guests do not belong to any domain (as in the case of Linux/Solaris guests) :  In this case, specify “none” in the Domain field, and specify a local administrator account name in the Admin User below.

    Prior to this, you need to ensure that the same local administrator account is available or is explicitly created on each of the virtual machines to be monitored. Then, proceed to provide the password of the Admin User against Admin Password, and confirm the password by retyping it in the Confirm Password text box.

    If key-based authentication is implemented between the eG agent and the SSH daemon of a Linux guest, then, in the Admin User text box, enter the name of the user whose <user_home_dir> (on that Linux guest) contains a .ssh directory with the public key file named authorized_keys. The Admin Password in this case will be the passphrase of the public key; the default public key file that is bundled with the eG agent takes the password eginnovations. Specify this as the Admin Password if you are using the default private/public key pair that is bundled with the eG agent to implement key-based authentication. On the other hand, if you are generating a new public/private key pair for this purpose, then use the passphrase that you provide while generating the pair. For the detailed procedure on Implementing Key-based Authentication refer to Troubleshooting the Failure of the eG Remote Agent to Connect to or Report Measures for Linux Guests.

  • If the guests 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 Paswords 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 Click here hyperlink that appears just above the parameters of this test in the test configuration page. To know how to use the special page, refer to Configuring Users for VM Monitoring.

  • If the inside view using flag is set to ‘eG VM Agent (Windows)’ - In this case, the inside view can be obtained without domain administrator privileges. Therefore, set the Domain, Admin User, and Admin Password parameters to none.

DD For Total VMS

By default, this flag is set to No. This means that the test will not report detailed metrics for the Total VMs measure by default. In large virtualized environments characterized by hundreds of VMs, this default setting will make sure that there is no unnecessary strain on the eG database. You can, if you so need, enable the test to report detailed metrics for this measure by setting this flag to Yes.

DD For Powered ON VMS

By default, this flag is set to Yes. This means that the test will report the complete list of powered on VMs as part of the detailed diagnosis of the Powered on VMs measure. To disable this capability for the Powered on VMs measure, set this flag to No.

DD Frequency

Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD frequency.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise 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 made by the test

Measurement

Description

Measurement Unit

Interpretation

Total VMs

Indicates the total number of VMs that have been registered with the Nutanix Prism Element.

Number

To know which VMs are registered with the Prism Element, use the detailed diagnosis capability of this measure (if enabled). Note that detailed metrics will be available for this measure only if the DD FOR TOTAL VMS flag is set to Yes.

Powered on VMs

Indicates the number of VMs that are currently powered on.

Number

To know which are the VMs that are powered on, use the detailed diagnosis capability of this measure (if enabled).

Powered off VMs

Indicates the number of powered off VMs on the monitored hypervisor.

Number

 

Suspended VMs

Indicates the number of VMs that are currently suspended.

Number

 

VMs with users

Indicates the number of powered on guests with users logged in.

Number

To know which guests the users have logged into, use the detailed diagnosis capability of this measure (if enabled). Note that this measure will not be available for the Nutanix AHV model.

Guests without users

Indicates the number of powered on guests without any users logged in.

Number

Note that this measure will not be available for the Nutanix AHV model.

Added VMs

Indicates the number of VMs that were newly added to the Nutanix AHV server during this measurement period.

Number

The detailed diagnosis of these measures, if enabled, lists the virtual machines that were migrated to or from (as the case may be) the Nutanix AHV server.

Removed VMs

Indicates the number of VMs that were newly removed from the Nutanix AHV server during this measurement period.

Number

The detailed diagnosis of the Powered on VMs measure, provides the complete list of VMs that are currently powered on.

Figure 1 : The detailed diagnosis of the Powered on VMs measure of a Nutanix AHV server

The detailed diagnosis of the Added VMs measure displays the IP address and operating system of those VMs that were recently migrated to the host.

Figure 2 : The detailed diagnosis of the Added VMs measure

The detailed diagnosis of the Removed VMs measure displays the IP address and operating system of the VMs that were recently removed/migrated from the host.

Figure 3 : The detailed diagnosis of the Removed VMs measure