Version 2.5 User's Guide
Defining Notifiers	Previous | Next Contents

The second type of object in PageSentry is the Notifier. When a Sentry has something to report it hands the task off to one or more Notifiers. To open the Notifier Editor dialog box, choose "Add Notifier..." from the Setup pull-down menu, or click the "Create New" button in the Object Manager. You may define up to 10 Notifiers in the standard version of PageSentry and up to 100 in PageSentry Pro, and each can be used on any or all of your Sentries.

The following section describes the various input fields and configuration options for the different methods that PageSentry uses to alert you to a problem. Figure 16 shows the PageSentry Notifier Editor dialog box.

Figure 16: Configuring a new E-Mail Notifier.

Common Elements

All four Notifiers, E-Mail, AppleEvent, PageNow!, and PowerKey Pro share the following configuration options:

Notification Name

The Notification Name is the name of the Notifier that appears in the Object Manager and Sentry editor lists. You can name a Notifier anything you like, since it has no effect on the notification process, but like a Sentry, each Notifier must have a unique name. Also, you should choose a name that you will be able to easily recognize when viewing the Edit Sentry window or the Object Manager.

Delay After Initial Failure

The Delay After Initial Failure setting allows you to have a Notifier wait a specified period of time after a Sentry encounters an error before actually performing its action. During the specified time, PageSentry will continue to test the server, and if the server returns to service, the Notifier will be disregarded without taking further action. There are several potential uses for this feature:

One use is to add an additional level of fault tolerance to your Sentries. By setting the Delay After Initial Failure to a period longer than your Sentry's test period, the delay will cause PageSentry to attempt the test multiple times. If a subsequent test of the server succeeds, the Notifier will not send an error report. By performing several tests during the delay, servers on slow or "flaky" networks may be monitored with greater tolerance.

Another use is to schedule escalating priorities for Notifiers. For example, you may have two Notifiers, one that sends e-mail to the server's primary support person without delay and another Notifier that sends e-mail to you using a 30 minute delay. When the server fails, the primary support person will be contacted immediately, and if the server is not fixed quickly, you will be notified shortly thereafter.

Another case of escalating Notifier priority is to use a PowerKey Pro to restart a Mac-based server by recycling its power. For example, you could have Notifiers send you an e-mail message and a page (using a PageNow! Sentry) immediately on failure, then wait 15 minutes before restarting the server. With this strategy, you will have time to investigate the server before the power is recycled.

Send "Back Up" Notice

In this context, "Back Up" means the server being monitored is "OK now." Checking this option causes the Notifier to send a second e-mail when the Sentry that had the original failure is testing OK again. "Back Up" notifications will only be performed when a failure notification has been previously sent to report a problem (unless "Always Send Back Up Notification" has been checked in the Notifiers Preferences).

Persistent Notices

This option causes the Notifier to repeat its action repeatedly, instead of acting only once for each server failure. When Persistent Notices is checked, the Notifier will repeat its action every time the Sentry detects a failure, even when that failure notice has already been sent. When this option is not checked, Notifiers will execute their defined action only once, and will not send another notice until the server returns to service.

Schedule Area

The last area on the notification editor window is the Schedule Area, where each grid square represents one hour. This grid allows you to define when the Notifier is active. Click in the boxes to toggle the state for that hour of that day, or click and drag to change multiple cells at once. When a Notifier is executed by a Sentry, the schedule is checked against the current system time and day of the week. If the hour is selected (red), then the Notifier will take its defined action. If the hour is not selected (gray), then no action is taken for that Notifier.

Note that each Sentry can have multiple notifications attached to it, so that other notifications may be sent, even if one Notifier's schedule does not match. You can make a staggering assortment of Notifiers for different people during lunch, weekends, Friday afternoons (whatever), and attach them all to the same Sentry. This Sentry would then send failure notification to different people or applications depending on when the failure occurred.

To congifure an E-Mail Notifier, select "E-Mail" from the Notifier Type list and fill in the following fields:

User Address

The User Address field contains a valid Internet e-mail address of the person receiving the Notification. This should be of the form "mailboxname@yourcom.com." If you are sending mail to an address that does not contain the "@" character between the user name and the host name, you will need to place the "<" and ">" characters around the address, as in "<bitnet!address!VMS!mainframe-2>."

Mail Server

The Mail Server field contains the domain name or IP address of the SMTP server that should be used to send the Notification e-mail. Most SMTP servers allow any client to send the server any piece of mail. The server will simply forward the mail to another (closer) mail server until it reaches its final destination. You should use a mail server designated by your network administrator or service provider. Your mail server will often reside on the machine with a name of the form "mail.yourcom.com".

You may want to enter the IP address of your e-mail server instead of the domain name, so if your DNS server fails, PageSentry will still be able to send e-mail notifications.

Mail From

The "Mail From" field contains the e-mail address from which the Notification will be sent. This address is important in case the e-mail cannot be delivered to the address entered in the "User Address" field. SMTP servers will try to route the piece of mail back to the specified Mail From address. It is best to set this to an e-mail address on a different e-mail server than the User Address, if possible.

You should always enter a valid Internet mail address in the Mail From field to prevent PageSentry's notification e-mail from becoming lost if it cannot be delivered to the User Address. Some mail servers (including AIMS and EIMS) will not accept messages without a valid "From" address.

Message

Clicking on the "Message" button brings up the dialog box shown in Figure 17, below. Here, enter any message text you like and use the six available "tokens" to configure the format of the email message you will receive from PageSentry. When the e-mail message is sent, the tokens will be replaced with information about the failed server. Both the Subject and Message Body of the e-mail message can be set.

Available tokens:

Sentry Name	This is the name of the Sentry that triggered the Notifier.
Notifier Name	The name of this Notifier.
Failed URL	The URL or server that has failed.
Error Desc	A brief description of the error that the Sentry encountered.
Date	The date the Notifier was triggered.
Time	The time the Notifier was triggered.

Figure 17: The E-Mail Message Configuration window.

Note that PageSentry connects directly to your Internet mail server and uses SMTP directly to send notifications. PageSentry E-Mail Notifiers will not work with other mail systems, unless PageSentry is set to send mail to an SMTP server, and an e-mail gateway is then used to route the mail to the appropriate mailbox.

Also keep in mind that notifications sent via e-mail will only be as timely as your mail system. For example, if your mail client does not frequently check for incoming mail messages, then notification e-mail messages may be delayed.

To have a Notifier send an AppleEvent to an AppleScript or another application, use the AppleEvent notifier. (For information about writing applications to receive and process AppleEvents sent from PageSentry, see the Extending PageSentry Using AppleEvents section in this Guide.)

Figure 18: The Notification section of the AppleEvent Notifier Editor dialog box.

The following are descriptions of the fields in the AppleEvent Notification section:

Application

This field contains the name of the application to which the AppleEvent is sent. It, or an alias, must be in the same folder as PageSentry. The filename should be the same as it appears in the Finder, with file and folder names separated with colons (":").

"Extra" Info

This field leaves room for a text message that is to be sent in the AppleEvent. Different applets will want different values in this field. Check the documentation of the applet or application to which you are sending the event.

Your PageSentry packages comes with several sample AppleScript Applet examples, including DisplayDialog. See the Read Me files that accompany each applet for information on using them with PageSentry.

PageSentry can interact directly with PageNow!, sending information directly to the application without having to create additional scripts.

Figure 19: The Notification section of the PageNow! Notifier Editor dialog box.

The following are descriptions of the fields in the PageNow! Notification section:

Subscriber Name

The name of the PageNow! subscriber goes here. This should be the same name that appears for the subscriber in the "Send To:" column of the PageNow! window.

Message

Clicking on the "Message" button displays a dialog box, shown in Figure 20, that allows you to configure how your message will appear. You can configure the six tokens here just as you would configure the e-mail message tokens. For more about the tokens, see E-mail Message Configuration, above.

Figure 20: The PageNow! Message Configuration window.

For more information on PageNow!, visit the MarkSpace Web site at http://www.markspace.com/.

PageSentry can directly control your Mac-based PowerKey Pro devices. This will allow you to configure a Notifier that, when triggered, can shut power down, wait a brief period, and restart power on a device or server connected to the PowerKey Pro. Recycling the power to a server in this way will restart a frozen or crashed server, no matter how badly the computer has crashed (except in the case of some hardware failures).

Figure 21 shows the PowerKey Pro section of the Edit Notifier window. Note that this Notifier type requires that the PowerKey software be installed on the Mac where PageSentry resides. Also, the ADB cable that controls the PowerKey must be plugged into the PageSentry computer. Servers to be restarted by the PowerKey and PageSentry are then plugged into the PowerKey strip.

A PowerKey notifier cannot be used to restart the PageSentry machine itself. If you do, PageSentry will shut power off for the computer, but will be unable to restart it. If you are running PageSentry on the same computer with an Internet server, use the PowerKey software to restart the computer instead. The Server Restart Option software is included with PowerKey Pro 600, and is available separately from Sophisticated Circuits for PowerKey or PowerKey Pro 200.

Figure 21: The Notification section of the PowerKey Pro Notifier Editor dialog box.

The following are descriptions of the fields in the PowerKey Pro Notification section:

Outlet Number

The outlets on a PowerKey Pro device are labeled with a number, 1 or 2 on the PowerKey Pro 200 and 1 through 6 on the PowerKey Pro 600. The device or server to be restarted will be plugged into one of these outlets. In the Outlet Number field, select the outlet to be recycled.

Unit Name

This is an optional field that allows you to input a name for PowerKey Pro unit that is to be recycled. If you have only one PowerKey unit, leave this field blank. If you have multiple units, see the PowerKey Configuration software for information on how to identify and name each of the attached units. Enter the name of the unit that controls the server you want to restart into this field.

For more information on PowerKey Pro, visit the Sophisticated Circuits website at http://www.sophisticated.com/.

Copyright © 1995-98 Maxum Development Corporation 820 South Bartlett Road - Suite 104 Streamwood, IL 60107 http://www.maxum.com/ Rev. 2/18/98	Previous | Next Contents