Availability Monitoring of HTML Pages with GRMG Lite
Do you want to monitor the availability and the content of URLs centrally? Then why not using the CCMS Monitoring Infrastructure? As of SAP NetWeaver 04 SPS 05, you can monitor a URL by creating a GRMG Lite scenario.
To create a GRMG Lite scenario, you need to enter a complete URL. You do not need to maintain any property values unless authentication is required. And you do not need to implement a GRMG application to use this function check, instead, GRMG Lite uses standard capabilities of the HTTP protocol.
As an example, you want to monitor the availability of the Object Server within the SLD. An SLD is a Java server application with which a client application communicates entirely using HTTP. The SLD server contains component information, system landscape descriptions, and a name reservation that are based on the Common Information Model (CIM) standard.
This is quite an advanced example, because using the URL, you need to authenticate yourself. And to check whether the Object Server is running, you have to check the content of the web page for the word Running. But… no pain, no gain.
- You call an SLD using http://<server>:<port>/sld; when you do so, you need to authenticate yourself.
You can determine whether the Object Server is running in the Administration area:
- Now you know the URL to be monitored. So, in the central monitoring system CEN, you start transaction GRMG and create a GRMG Lite scenario.
You now enter the names and descriptions of the scenario and its component (use any name you like). GRMG Lite is grouped by scenarios, where each scenario can contain different components. The results of the availability monitoring are displayed as a separate subtree in the Alert Monitor.
Apply your entries by pressing the Create button.
The names, which can be a maximum of eight characters long, become part of the MTE class name of the nodes in the Alert Monitor.
The descriptions determine the node names of the subtrees in the Alert Monitor; they must be unique.
Leave the Version input field blank.
3. Now enter the URL that you want to monitor.
|USE_BASIC_AUTHENTICATION||type X if you want to authenticate yourself with a user name and password|
|LOGON_PASSWORD||password of the user above; you should set the property type to PW so that the password is stored in encrypted format in the secure storage, is displayed with asterisks, and is protected by other security measures
\ In NW04 you need to maintain a password with property type PW in client 000, otherwise the CCMS dispatcher won’t be able to read it.
1. Scroll down in the list of editable properties. Now you want to set the properties necessary for checking the content of the page.
|GET_OR_HEAD||type GET if you want to monitor not only the header data, but also the content of an HTML page|
|CHECK_STRING_1||enter the desired character string; here you expect Running. An alert is to be generated if the character string does not appear in the page.|
|CHECK_STRING_2||here, you want to monitor the page for another character string, Stopped. However, in this case, an alert is to be displayed if the character string appears in the page. You can do this by placing an exclamation point ! in front of the character string.|
To save the scenario, choose the Save button.
You have created the scenario. To start the scenario, select it, and choose the Start button.
You can see from the icon in the Run column that the scenario has been successfully run. This does not necessarily mean that the checked page is available. It just means that the check itself was successfully performed.
Now start the Alert Monitor (transaction RZ20). You can find the results of the availability monitoring with GRMG Lite in the Availability and Performance Overview monitor, monitor set SAP CCMS Monitor Templates.
The Availability SLD subtree is displayed.
You can see that the subtree consists of two parts:
A subtree for the self-monitoring of the scenario. This part shows whether the availability check itself was performed successfully.
A subtree for each monitored component. You can see from the color of the node Availability that the web page is available; this means that the HTTP return code is ok or redirect. Besides, the string Stopped was not found in the page.
Now, let’s check the monitoring. Stopp the Object Server on the monitored URL by choosing the Stop Server button.
- Back in the Alert Monitor, the Availability still is 100% (because the HTTP code is still ok), but the string Stopped is found in the page, so a red alert is raised.
That’s it! Now the availability of the SLD is monitored in the central monitoring system; Moreover, the status of the Object Server is checked via the content of the web page.