Disk Alignment – OS Test

Time synchronization is one of the most important dependencies of windows. A time protocol is responsible for determining the best available time information and converging the clocks to ensure that a consistent time is maintained across systems. By default, windows support a tolerance of plus or minus five minutes for clocks. If the time variance exceeds this setting, clients will be unable to authenticate and in the case of domain controllers, replication will not occur. It implements a time synchronization system based on Network Time Protocol (NTP).

NTP is a fault-tolerant, highly scalable time protocol and it is used for synchronizing computer clocks by using a designated reference clock. A reference clock is some device or machinery that spits out the current time. The special thing about these things is accuracy. Reference clocks must be accurately following some time standard. NTP will compute some additional statistical values based on the current time reported by the reference clock, which will describe the quality of time it sees. Among these values are: offset (or phase), jitter (or dispersion), frequency error, and stability. Thus each NTP server will maintain an estimate of the quality of its reference clocks and of itself.

This test reports the time difference between the reference clock and that of the target environment, and thus helps assess the quality of time seen by the Windows VM. With the help of this test, you can also easily determine whether the reference time changed recently.

Note:

This test reports metrics for Windows VMs only.

This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick KVM Server as the desired Component type, set Performance as the Test type, choose the test from the disabled tests list, and click on the < button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : A KVM server

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each disk partition on every Windows VM on a KVM server host being monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.

Host

The IP address of the host for which this test is to be configured.

Port

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

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 VMstext 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 VMware 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 KVM 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 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 to Configuring the Remote Agent to Obtain the Inside View of Windows VMs, using the eG VM Agent 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 the Inside 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 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 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 Disk Alignment – OS Test.
  • 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.

Report By User

For the KVM server monitoring model, the Report By User flag is set to No by default, indicating that by default, the guest operating systems on the KVM server are identified using the hostname specified in the operating system. On the other hand, while monitoring KVM VDI environments, this flag is set to Yes by default; this implies that in case of VDI servers, by default, the guests will be identified using the login of the user who is accessing the guest OS. In other words, in VDI environments, this test will, by default, report measures for every username_on_virtualmachinename.

Report Powered OS

This flag becomes relevant only if the Report By User flag is set to ‘Yes’.

If the Report Powered OS flag is set to Yes (which is the default setting), then this test will report measures for even those VMs that do not have any users logged in currently. Such guests will be identified by their virtualmachine name and not by the username_on_virtualmachinename. On the other hand, if the Report Powered OS flag is set to No, then this test will not report measures for those VMs to which no users are logged in currently.

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

Disk partition alignment status

Indicates whether this disk partition is aligned or not.

 

If the partition is unaligned, this test reports the value Partition is not aligned. For an aligned partition, this test reports the value Partition is aligned.

The numeric values that correspond to the above-mentioned measure values are described in the table below:

Measure Value Numeric Value
Partition is aligned 100
Partition is not aligned 0

Note:

By default, this measure reports one of the Measure Values listed in the table above. The graph of this measure however will represent the disk alignment status using the numeric equivalents - 100 or 0.

If a partition is found to be misaligned, you can use the detailed diagnosis of this test to figure out the caption, device ID, logical partition name, and block size of the faulty partition.