Agents Administration - Tests
 

Configuration of XenIntCacheTest

This test continuously tracks the usage of the read and write caches in each of the local storage repositories and reports whether/not the caches are able to service most of the I/O requests to the shared storage, without actually accessing the shared storage! This way, administrators will be able to figure out whether/not the caches effectively serve the purpose they were intended for. In addition, the test also checks and reports the current cache size, so that administrators can judge its adequacy and make changes, if required.

Note:

The performance metrics reported by this test are enabled by default in the XenServer 6.1.0 Performance and Monitoring Supplemental Pack. In XenServer 6.2.0 however, these metrics, though part of the core product, are disabled by default, owing to performance reasons related to XenCenter. This means that, when monitoring XenServer 6.2.0, this test will not report any metrics by default. In such cases, to make sure that the test reports metrics, do the following:

  • Login to the XenServer host as root user.

  • Enable the metrics by issuing the following command from the CLI:

    xe-enable-all-plugin-metrics true

The default parameters associated with this test are as follows:

  • The TEST PERIOD list box helps the user to decide how often this test needs to be executed.

  • In the HOST text box, the host name of the server for which the test is to be configured has to be specified.

  • To enable the eG agent to connect to the XenServer API for collecting statistics of interest, this test should login to the XenServer as a root user. Provide the name of the root user in the XEN USER text box. Root user privileges are mandatory when monitoring a XenServer 5.5 (or below). However, if you are monitoring XenServer 5.6 (or above) and you prefer not to expose the credentials of the root user, then, you have the option of configuring a user with pool-admin privileges as the XEN USER. If you do not want to expose the credentials of a root/pool-admin user, then you can configure the tests with the credentials of a XEN USER with Read-only privileges to the XenServer. However, if this is done, then the Xen Uptime test will not run, and the Xen CPU and Xen Memory tests will not be able to report metrics for the control domain descriptor. To avoid such an outcome, do the following before attempting to configure the eG tests with a XEN USER who has Read-only privileges to the XenServer:

    • Modify the target XenServer's configuration in the eG Enterprise system. For this, follow the Infrastructure -> Components -> Add/Modify menu sequence, pick Citrix XenServer as the Component type, and click the Modify button corresponding to the target XenServer.
    • In the MODIFY COMPONENT DETAILS page that then appears, make sure that the OS is set to Xen and the Mode is set to SSH.
    • Then, in the same page, proceed to provide the User and Password of a user who has the right to connect to the XenServer console via SSH.
    • Then, click the Update button to save the changes.

    Once this is done, you can configure the eG tests with the credentials of a XEN USER with Read-only privileges.

  • Specify the password of the specified XEN USER in the XEN PASSWORD text box.

  • Confirm the password by retyping it in the CONFIRM PASSWORD text box.

  • By default, the Xen Server is not SSL-enabled. This indicates that by default, the eG agent communicates with the XenServer using HTTP. Accordingly, the SSL flag is set to No by default. If you configure the XenServer to use SSL, then make sure that the SSL flag is set to Yes, so that the eG agent communicates with the XenServer using HTTPS. Note that a default SSL certificate comes bundled with every XenServer installation. If you want the eG agent to use this default certificate for communicating with an SSL-enabled XenServer, then no additional configuration is required. However, if you do not want to use the default certificate, then you can generate a self-signed certificate for use by the XenServer. In such a case, you need to explicitly follow the broad steps given below to enable the eG agent to communicate with the XenServer via HTTPS:

    • Obtain the server-certificate for the XenServer
    • Import the server-certificate into the local certificate store of the eG agent

    For a detailed discussion on each of these steps, refer to the Troubleshooting section of the Monitoring Xen Servers document.

  • By default, in most virtualized environments, the XenServer listens on port 80 (if not SSL-enabled) or on port 443 (if SSL-enabled). This implies that while monitoring an SSL-enabled XenServer, the eG agent, by default, connects to port 443 of the server to pull out metrics, and while monitoring a non-SSL-enabled XenServer, the eG agent connects to port 80. Accordingly, the WEBPORT parameter is set to 80 or 443 depending upon the status of the SSL flag. In some environments however, the default ports 80 or 443 might not apply. In such a case, against the WEBPORT parameter, you can specify the exact port at which the XenServer in your environment listens so that the eG agent communicates with that port.

  • If multiple components of the same component type are awaiting configuration, then an APPLY TO OTHER COMPONENTS check box will appear in this page. Clicking on this check box will allow you to apply the configuration to all/selected components of that type.

  • Once the necessary values have been provided, clicking on the Update button will register the changes made.

When changing the configuration for specific servers, a “*” beside the text box corresponding to the parameter signifies that these values have to be manually configured by the user. The parameter values that require to be configured will typically be prefixed with a *ldquo;$” or contain a series of “*”. A value of "none" in the parameter value indicates that the corresponding parameter value can be changed if required.