What can be done to to inform an administrator when an unacceptably of virtual machines are being deployed usi

A group of virtual machine has been deployed using the disk because of limited storage space availability. The storage team has expressed concern about extensive use of this type of provisioning.

What can be done to to inform an administrator when an unacceptably of virtual machines are being deployed using thin-disk provisioning?

A.
Modify the default datastore usage on disk alarm with a determined percentage. Create a trigger for the alarm with an email or SNMP notification option.

B.
Use the default host storage Status alarm. Crate a trigger for the alarm with an emailor SNMP notification option.

C.
Find the predefined Thin-Provisioned LUN Capacity Exceeded alarm for each datastore. Set an action to enable the email or SNMP notification option.

D.
Create an alarm for Disk Usage and determine the appropriate amount. Create a trigger for the alarm with an email or SNMP notification option.

Explanation:
http://pubs.vmware.com/vsphere-50/index.jsp?topic=/com.vmware.vsphere.solutions.doc_50/GUID-6B51A3FE-ABBC-4495-B12D-7F0949ECE7F3.html

Dozens of default alarm definitions are provided by the vSphere Client, which you can locate in the Alarms tab for an inventory object. One of these default alarms is Datastore usage on disk, which you use to monitor the percentage of disk usage. This kind of alarm is important if the virtual machines in the datastore have virtual disks in the thin provisioned format. With thin provisioning, at first a thin provisioned disk uses only as much datastore space as the disk initially needs. However, if the thin disk needs more space later, it can grow to the maximum capacity allocated to it.
With thin provisioning, it is possible to oversubscribe storage space if the virtual machines grow unattended. An alarm set on the datastore can notify you when the space issues threaten to become critical.

5 Comments on “What can be done to to inform an administrator when an unacceptably of virtual machines are being deployed usi

  1. G.D says:

    There is a predefine alarm on vcenter: Thin-Provisioned LUN Capacity Exceeded alarm:

    Find the predefined Thin-Provisioned LUN Capacity Exceeded alarm for each datastore. Set an action to enable the email or SNMP notification option.

    1. asdf says:

      the question is regarding VM thin provisioning. the “thin-provisioned lun capacity exceeded alarm” is regarding thin provisioning on the storage array itself. therfore, A is the correct answer

  2. TwojaStara04 says:

    A group of ABC virtual machines has been deployed using thin disks due to limited
    storage space availability. The storage team has expressed concern about extensive use of
    this type of provisioning. Which of the following actions can be taken to inform an
    administrator when an unacceptably large number of virtual machines are being deployed
    using thin disk provisioning?

    A.
    Modify the default Datastore Usage on Disk alarm with a determined percentage.
    Create a trigger For the alarm with an e-mail or SNMP notification option.

    B.
    Use the default Host Storage Status alarm. Create a trigger for the alarm with an
    e-mail or SNMP notification option.

    *C.
    Create an alarm for Datastore Disk Overallocation and determine an appropriate
    percentage. Create A trigger for the alarm with an e-mail or SNMP notification option.

    D.
    Create an alarm for Disk Usage and determine the appropriate amount. Create a
    trigger for the Alarm with an e-mail or SNMP notification option.

  3. TwojaStara04 says:

    Monitor your data store free space carefully. There is a new alarm in vSphere to monitor data store free space called Datastore Usage on Disk that will alert you when your data store disk space usage grows to a defined percentage. Additionally there is another alarm that you can set called Datastore Disk Overallocation % which will trigger when your disk space over-allocation reaches a defined limit (i.e. 300%).
    http://itknowledgeexchange.techtarget.com/virtualization-pro/pointers-for-using-thin-provisioned-disks/

    We recommend setting alarm triggers on Datastore Disk Usage % and also on Datastore Disk Overallocation % to assist in management thin provisioned datastores and overcommitment.
    http://www.vmware.com/pdf/vsp_4_thinprov_perf.pdf

    Datastore Disk Overallocation (%) – Amount of overallocated disk space in the datastore.
    Datastore Disk Usage (%) – Amount of disk space (KB) used by the datastore. This alarm controls the Status value for datastores in vSphere Client. If you disable this alarm, the datastore status will be displayed as Unknown.
    http://pubs.vmware.com/vsphere-4-esx-vcenter/index.jsp?topic=/com.vmware.vsphere.dcadmin.doc_41/vsp_dc_admin_guide/working_with_alarms/r_condition_state_triggers_datastores.html

    Using datastore alarms and errors to determine your available space is pretty straight forward. The default alarm Datastore usage on disk is the perfect alarm to use, and it’s enabled by default
    The Datastore usage on disk alarm is pre-configured to trigger a warning when its disk usage is over 75%. It will trigger an alert if it gets above 85%. Now again, these are the defaults for this alarm, you may want to edit the thresholds based on your organizations best practices as it relates to %free for storage
    http://www.valcolabs.com/category/storage/

    Consider creating these custom alarms on the folders where critical VMs. Optionally, define email actions on some of these.
    Datastore Disk Provisioned (%) (set yellow trigger to 100%, where the provisioned disk space meets or exceeds the capacity.)
    http://vloreblog.com/2014/02/07/custom-vcenter-server-alarms-and-actions/

    Summary:
    I don’t see in vCenter 5.1 predefined alarm or custom trigger like “Datastore Disk Overallocation”. I thin it was in vC 4.0 but now its renamed to “Datastore Disk Provisioned” and is custom trigger. Default predefined allarm to monitor used space is “Datastore Disk Usage”.


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