Tuesday, January 8, 2008

Monitors in Server Manager

Monitors


Most of my posts thus far have been about installation, troubleshooting, and other server manager basics. Today begins a series of posts outlining the new or enhanced capabilities provided by SM.


Monitors are the mechanism by which administrators can be alerted through e-mail when an event of interest occurs. Much of this functionality is a direct carryover from that provided by the SAW SMC infrastructure in previous tools releases with some significant enhancements to boot.


As you may be aware by now Server Manager is a complete replacement for SAW and SMC. Among the other benefits, such as deployment and configuration management, we wanted to enhance and make easier to use the functionality provided by the SAW application.


While evaluating the SMC monitoring capabilities we identified the need to improve it in the following ways:

* Simplify the setup required to monitor servers and configure events of interest

* Enhance the monitored events to include some key items of interest, such as a user being unable to login to the E1 HTML Server

* Permit configuration of the hours in which alert e-mails should be sent for sites that make use of multiple administrators that are responsible for particular times of the week

* Maintain a history of past events and record the e-mail messages that were sent


We also changed the mechanism by which the events of interest are obtained. Beginning with 8.97 our server products contain an embedded variant of the management agent that provides server manager with the runtime information about the servers. Using this mechanism to obtain events provided two primary benefits: many of the events are reported to SM immediately upon occuring and events can be obtained from clustered or multi-JVM configurations for our web based products.


Currently monitoring is supported for our enterprise server and HTML server products only.


To get started select the monitors link from the quicklinks section. Note you must be signed into the management console as the jde_admin user or another user that as been granted the 'monitorConfig' permission to make changes to the monitoring configuration.


SMTP Configuration


The first step is to configure the SMTP mail server that will be used by server manager to send emails. Simply supply the mail server name, TCP/IP port to use, and sender email to use as the 'from' address. Some SMTP servers may require the sender email be from the same domain the mail server is configured to use. Note: SMTP servers that require authentication to send emails is not currently supported.


After making any changes you may supply an email address to test the settings. Server Manager will send an email to the supplied address to ensure the mail server configuration is correct.


Getting Started


The next step is to create a new monitor. You may have as many monitors as you wish. For example you may wish to create multiple monitors that listen for different events and each have different email recipients. Enter a name for the new monitor and select the 'Create' button. You will be redirected to a page used to configure the newly created monitor.


The first option in the general settings controls how often the monitor should poll for events. Some events will be detected immediately; when they occur a notification is sent to the management console and then to each running monitor. If this event is enabled for a particular monitor an email will be sent immediately. Other events are polled on a periodic basis. For example checking the free disk space on an enterprise server occurs on this period poll. You can change the frequency in which the monitor will check for these events.



Checking for monitored events is a low impact activity. That said if you have a large number of monitors it may be advisable to increase this interval from the default of 30 seconds.


Secondly you may configure whether this monitor should be automatically started when the management console application is started. Regardless of this selection an authorized user may start and stop monitors at any time using the previous page.


Instance Selection


The next step involves selecting the managed instances that this monitor should observe. Simply move the desired instances from the available options list to the selected options. Note that any changes made here on a running monitor will take effect immediately; the monitor need not be restarted.



Event Selection


Now that we have selected which managed instances we should monitor we now need to select which events we wish to observe. You do so by simply selecting the events of interest in the next section of the page. Each event has a help box next to it describing what the event is and when it may occur.



Some events may have threshold values that allow you to define a limit that, once reached, will trigger an email notification. The example below shows the limits for simultaneous users.



Once a threshold limit is reached on an enabled event a email notification will be sent. Notifications will not be resent unless the threshold goes higher. Consider the simultaneous users event. If we set the threshold to 50 we would receive a notification once 50 users are on at the same time. If two users sign off and two new users sign back on we are back at 50 simultaneous users. An email will not be sent; an email for 50 users has already been sent. If another user signs on, so we are at 51 sessions, and email will be sent; we have gone higher then the highest threshold reached.


I won't go into what all the events are in this post; they are documented with online help within the application.


Notification Hours


For a particular monitor you may specify which hours in the day and which days of the week email notifications should be sent. This may be helpful for those who administer in shifts. Those interested in events on weekdays may be different then those interested in weekend events, for example.



When you create a new monitor the default will be to enable notifications for all hours of all days. You can change this by modifying the times for each day using 24 hour notation. To disable events for an entire day simply set the start time and end time to both be 00:00.


The management console will use the clock and time zone information provided by the JVM on which it runs. That is the times should be considered to be the times as known to the management console machine.


Email Recipients


Finally we specify the email recipients that should receive notifications. You may add as many recipients as you wish. Any changes made to this list will take effect immediately; you need not restart the monitor.



Emails are sent individually to each recipient defined for a monitor using the from address configured previously. The subject and content of the email will contain details of the event. The mail format is plain text and is suitable for email, pager, and SMS mailboxes.



If an email could not be sent for any reason the failure will be recorded in the monitor's history, as discussed below.

Monitor History


Server Manager maintains a history for each monitor. Each start of a monitor will be listed in the monitor history.



You may view the history of a particular monitor to see all the events that occurred and the emails sent by clicking the appropriate icon in the grid row.



Each event that occurred will be listed along with the same type if information that was contained in the email sent. A grid will contain a listing for each email recipient of the monitor showing the successful sending of the email, an email that wasn't sent because it was outside the notification hours configured, or a email that failed to send for some reason such as an invalid recipient.


You may delete the monitor history if you no longer wish to view it. You may not delete the history for an actively running monitor.


Cloning Monitors


We have made it easy to clone an existing monitor. Simply select the corresponding icon in the 'Create Duplicate' column in the list of available monitors.



All the settings, selected managed instances, events, notification hours, and email recipients from the selected monitor will be copied to a new monitor definition. This makes setting up monitors for shifts much easier; the events and other setup need not be configured multiple times.


Summary


Hopefully you see that setting up and using monitors in Server Manager is much easier than previous solutions and the added events make administering your E1 servers much easier. Dig in, play with monitors, and enjoy.


UPDATE: I think the issue with missing images has been resolved.