With the cluster validation wizard, you can run a set of
focused tests on a collection of servers that are planned for use as
cluster nodes. The cluster validation process tests the underlying
hardware and software directly, and individually, to obtain an accurate
assessment of how well failover clustering can be supported on a given
configuration.
Cluster validation is intended to catch hardware or
configuration problems before the cluster goes into production. Cluster
validation helps to ensure that the solution you are about to deploy is
truly dependable. Cluster validation can also be performed on configured
failover clusters as a diagnostic tool.
 Important |
|---|
| Before you create a failover cluster, we strongly recommend that you run all tests in the cluster validation wizard. |
When you perform cluster validation on an already
configured cluster, you might not always run all tests. If you include
storage tests in the set of tests you run, there are different
considerations to keep in mind than if you do not include storage tests.
This section outlines the main considerations:
-
Considerations when including storage tests:
When cluster validation is performed on an already configured cluster,
if the default tests (which include storage tests) are selected, only
disk resources that are in an Offline state or are not assigned to a
clustered service or application will be used for testing the storage.
This builds in a safety mechanism, and the cluster validation wizard
warns you when storage tests have been selected but will not run on
storage in an Online state, that is, storage used by clustered services
or applications. This is by design to avoid disruption to highly
available services or applications that depend upon these disk resources
being online.
One scenario where Microsoft CSS may request you to run validation tests on production clusters is when there is a cluster storage failure that could be caused by some underlying storage configuration change or failure. By default, the wizard warns you if storage tests have been selected but will not be run on storage that is online, that is, storage used by clustered services or applications. In this situation, you can run validation tests (including storage tests) by creating or choosing a new logical unit number (LUN) from the same shared storage device and presenting it to all nodes. By testing this LUN, you can avoid disruption to clustered services and applications already online within the cluster and still test the underlying storage subsystem.
If a failover cluster passed the full set of validation tests and has no future hardware or software changes, then it will continue to be a supported configuration. However, when you perform routine updates to software components such as drivers and firmware, it may be necessary to re-run the validation wizard to ensure that the current configuration of the failover cluster is supported. The following guidelines can help in this process:-
All components of the storage stack should be identical
across all nodes in the cluster. It is required that multipath I/O
(MPIO) software and Device Specific Module (DSM) software components be
identical. It is recommended that the mass-storage device
controllers—that is, the host bus adapter (HBA), HBA drivers, and HBA
firmware—that are attached to cluster storage be identical. If you use
dissimilar HBAs, you should verify with the storage vendor that you are
following their supported or recommended configurations.
-
To minimize impact to highly available applications and
services, a best practice is to keep a small LUN available to allow the
validation wizard to run tests on available storage without negatively
impacting clustered services and applications. This way, if Microsoft
CSS requests you to run a full set of cluster validation tests, the
wizard will follow the default behavior and run tests on the available
storage (the new LUN only).
-
All components of the storage stack should be identical
across all nodes in the cluster. It is required that multipath I/O
(MPIO) software and Device Specific Module (DSM) software components be
identical. It is recommended that the mass-storage device
controllers—that is, the host bus adapter (HBA), HBA drivers, and HBA
firmware—that are attached to cluster storage be identical. If you use
dissimilar HBAs, you should verify with the storage vendor that you are
following their supported or recommended configurations.
-
Considerations when not including storage tests:
System configuration tests, inventory tests, and network tests have
very low overhead, and can be performed without significant effect on
servers in a cluster.
Microsoft CSS may request you to run the cluster validation on a production cluster as part of normal troubleshooting procedures (not focused on storage). In this scenario, you will use the wizard to inventory hardware and software, perform network testing, and validate system configuration. There may be certain scenarios in which only a subset of the full tests are needed. For example, if troubleshooting a problem with networking on a production cluster, Microsoft CSS may request that you run only the hardware and software inventory and the network tests.
Microsoft will help you collect the validation report
through the Microsoft Support Diagnostic Tool (MSDT), which is the
replacement for the MPSReports data collection utility. Microsoft CSS
will send the MSDT via e-mail with instructions on how to capture the
data. In some situations, Microsoft CSS may request that the contents of
the C:\Windows\Cluster\Reports folder be zipped and sent in for
analysis. Either method will collect the required cluster validation
report.
-
Identify the server or servers that you want to test and confirm that the failover cluster feature is installed:
-
If the cluster does not yet exist, choose the servers that
you want to include in the cluster, and make sure you have installed the
failover cluster feature on those servers. To install the feature, on a
server running Windows Server 2008 or Windows Server 2008 R2, click Start, click Administrative Tools, click Server Manager, and under Features Summary, click Add Features. Use the Add Features wizard to add the Failover Clustering feature.
-
If the cluster already exists, make sure that you know the name of the cluster or a node in the cluster.
-
If the cluster does not yet exist, choose the servers that
you want to include in the cluster, and make sure you have installed the
failover cluster feature on those servers. To install the feature, on a
server running Windows Server 2008 or Windows Server 2008 R2, click Start, click Administrative Tools, click Server Manager, and under Features Summary, click Add Features. Use the Add Features wizard to add the Failover Clustering feature.
-
Review network or storage hardware that you want to
validate, to confirm that it is connected to the servers. For more
information, see http://go.microsoft.com/fwlink/?LinkId=111555.
-
Decide whether you want to run all or only some of the
available validation tests. For detailed information about the tests,
see the topics listed in http://go.microsoft.com/fwlink/?LinkId=111554.
The following guidelines can help you decide whether to run all tests:
-
For a planned cluster with all hardware connected: Run all tests.
-
For a planned cluster with parts of the hardware connected:
Run System Configuration tests, Inventory tests, and tests that apply
to the hardware that is connected (that is, Network tests if the network
is connected or Storage tests if the storage is connected).
-
For a cluster to which you plan to add a server:
Run all tests. Before you run them, be sure to connect the networks and
storage for all servers that you plan to have in the cluster.
-
For troubleshooting an existing cluster:
If you are troubleshooting an existing cluster, you might run all
tests, although you could run only the tests that relate to the apparent
issue.
Important If a clustered service or application is using a disk when you start the wizard, the wizard will prompt you about whether to take that clustered service or application offline for the purposes of testing. If you choose to take a clustered service or application offline, it will remain offline until the tests finish.
-
For a planned cluster with all hardware connected: Run all tests.
-
In the failover cluster snap-in, in the console tree, make sure Failover Cluster Management is selected and then, under Management, click Validate a Configuration.
-
Follow the instructions in the wizard to specify the servers and the tests, and run the tests.
Note that when you run the cluster validation wizard on unclustered servers, you must enter the names of all the servers you want to test, not just one.
The Summary page appears after the tests run.
-
While still on the Summary page, click View Report to view the test results.
To view the results of the tests after you close the wizard, see SystemRoot\Cluster\Reports\Validation Report date and time.html where SystemRoot is the folder in which the operating system is installed (for example, C:\Windows).
-
To view Help topics that will help you interpret the results, click More about cluster validation tests.
To view Help topics about cluster validation after you close the wizard, in the failover cluster snap-in, click Help, click Help Topics, click the Contents tab, expand the contents for the failover cluster Help, and click Validating a Failover Cluster Configuration.
Source:
technet.microsoft.com
Published By
S.G.Godwin Dinesh.MCA
Sr.System Administrator
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