### Human: Can you tell about NCC Health Check: ahv_version_check. ### Assistant: The NCC health check ahv_version_check checks if the AHV version bundled with the currently installed AOS is not yet installed on the cluster.. The NCC health check ahv_version_check checks if the AHV version bundled with the currently installed AOS is not yet installed on the cluster.

After upgrading AOS, a bundled compatible AHV version is present and available for immediate upgrade in Prism. It is recommended that this bundled version of AHV, at a minimum, is installed at the earliest convenience to avoid potential compatibility issues in the future. This NCC check verifies if there were AOS upgrades performed on a cluster without a corresponding AHV upgrade, and raises awareness of the fact. 

Running NCC Check

You can run this check as a part of the complete NCC Health Checks.
	nutanix@cvm$ ncc health_checks run_all
	Or you can run this check separately.
	nutanix@cvm$ ncc health_checks run_all
	

You can also run the checks from the Prism web console Health page: select Actions > Run Checks. Select All checks and click Run.

This check is scheduled to run every day, by default.

This check will generate an alert after 1 failure.

Sample Output

Check Status: PASS

nutanix@cvm$ ncc health_checks run_all

Check Status: FAIL

nutanix@cvm$ ncc health_checks run_all

Check Status: ERROR

nutanix@cvm$ ncc health_checks run_all

Check Status: WARNING 

nutanix@cvm$ ncc health_checks run_all
NOTE: If you see this WARN output or Alert in an NC2 on AWS cluster, it is false-positive and you can safely disregard it. However, it is advisable to upgrade AOS to 6.0.2.5 or above to resolve this issue.  

Output messaging

Check ID111061DescriptionCheck if a compatible AHV version is installed on the host.Causes of failureThe installed AHV version is not compatible with the current AOS version.ResolutionsUpgrade the version of AHV on the host to a version that is compatible with the current AOS version.ImpactAHV is not running with the full set of features.Alert TitleDetected incompatible AHV versionAlert MessageUpgrade the version of AHV on the host to desired_veror_later.a host.. If this check fails with the error below, the currently installed AHV version on the cluster is not the expected version with the AOS:

AHV currently is installed with <installed version>, it should be installed with <expected version> or a compatible version
 

Checking Installed AOS Version

Prism: Click on your user name in the top right corner and select the "About Nutanix" menu option.Command-line: 
	AHV currently is installed with <installed version>, it should be installed with <expected version> or a compatible version
	

Upgrade AHV

Perform the following steps to check the expected AHV version and upgrade AHV.

Check the "Software Installed in This Release Family" section of release notes for the currently installed AOS version on Nutanix Portal to find a compatible AHV version. Upgrade AHV by following the steps described in the "AHV upgrade" section of "Prism Web Console Guide".After upgrading the AHV version, run the check again, and the result should be a PASS output.

If this check fails with the error below it means that NCC could not retrieve information about the AHV version that is compatible with the current AOS release:

AHV currently is installed with <installed version>, it should be installed with <expected version> or a compatible version
To confirm this issue run the following command to check if any data is present in /home/nutanix/data/installer/ folder:

AHV currently is installed with <installed version>, it should be installed with <expected version> or a compatible version

If the folder is empty consider upgrading AOS to the latest release. During upgrade /home/nutanix/data/installer/ folder will be automatically populated with correct data.

Known issueAfter an upgrade to AOS 5.19 or 5.19.0.5, you may notice an alert suggesting to upgrade AHV from 20190916.360 to 20201105.12 or 20201105.1021, while LCM is not offering any new AHV releases.Upgrades from AHV 20190916.360 to 20201105.12 and 20201105.1021 were blocked because 20190916.360 was released after 20201105.12/1021 and as a result target AHV versions are older than the source version. If an upgrade is allowed then it may actually lead to downgrading the version of some packages.After AOS upgrade to 5.19.1 LCM will start offering to upgrade AHV to version 20201105.1045.For NC2 on AWS cluster, a false-positive ncc WARN will be displayed. This is due to AHV version 20201105.30007 was blacklisted as an available option to upgrade. This affects AOS versions 6.0.2, 6.0.2.2 and 6.0.2.4, where said AHV version was bundled with these AOS releases. If the above steps do not resolve your issue, consider engaging Nutanix Support for further assistance.. ### Human: Now explain this as a Nutanix support agent summarizing the answer step by step. In case, you don't know the answer say - I don't know.