Version 4.1 User's Guide
Defining Sentries	Previous | Next Contents

To monitor an Internet server, you will first need to define a new Sentry. To open the Sentry Configuration dialog box, click "Create New" on the Sentry section of the Object Manager, or choose "New Sentry" from the "Sentries" pull-down menu. Select the type of server you want to monitor using the "Sentry Type" pop-up menu on the Sentry Configuration window. You can have different Sentries monitor a different Internet service running on a single server, one service running on different servers, or any combination of the two. The following section describes the various input fields and configuration options for the different types of Internet servers that PageSentry is capable of monitoring.

Common Elements

Each type of Sentry is configured in three parts. The upper half of the Edit Sentry window details how the Sentry is configured and the bottom half of the window is used to select and deselect Notifiers to be triggered when a Sentry encounters an error. We will talk about the Notifiers in detail in the section entitled "Defining Notifiers". Each Sentry uses a slightly different combination of input fields in the top half of the Configuration screen, but they all include the following fields:

Sentry Name

This is the name that will be reported in an e-mail message or AppleEvent notification, and this name will also be shown in the Object Manager and Status Window. You can name a Sentry anything you like, since it has no effect on the server check, but each Sentry must have a unique name. Also, you should choose a name that you will be able to easily recognize when the Sentry notifies you of a problem, such as "Primary Web Server" or "E-mail Server".

Group

Sentries can be grouped together to trigger a single Notifier or for reporting purposes. For complete details, see the "Defining Groups" section of this User's Guide. Once one or more groups have been defined, you can select which (if any) the Sentry is assigned to by selecting the Group name from the pop-up menu.

Log File

The Log File is where a particular Sentry will store a record of its activities. Each Sentry can log to a different file, or any number of Sentries can be configured to use the same log file. To log entries to a new log file, just type the name of the new log file in the Log File field and it will be created automatically. Leaving this field blank prevents PageSentry from logging anything for this Sentry. Log files will always be created in the same folder as the PageSentry application.

Frequency

The Frequency setting will determine how often PageSentry will test the server (or send a status report, in the case of Pulse Sentries).

Note that a single request does not usually require a great deal of processing by a server, so there is little performance penalty in having PageSentry check your server fairly often. In general, having PageSentry test a server every 3 to 10 minutes will give you timely notification without imposing a noticeable load on your server.

Execute Test

Each Sentry type except Pulse also has an "Execute Test" button that lets you immediately run the test defined for the Sentry. The ability to run Sentry tests immediately gives you an easy way to verify that you have created the Sentry correctly. When the test completes, a dialog will be displayed showing the results of the test. Notifiers that are attached to the Sentry will not be executed in the event of a failure.

For FTP Sentries, running the test also automatically fills in the checksum and length fields, saving you from having to compute these manually. Executing the test of a DNS Sentry will automatically populate the IP Address field. The Stream Sentry will also compute the checksum when the "Execute Test" button is pressed.

Set Schedule

Usually, Sentries run their tests at the defined frequency 24 hours a day, 7 days a week. However, there may be cases where you would prefer a Sentry to suspend testing at a scheduled time. For example, service may be interrupted when a file server is backed up each Tuesday night at 2 a.m. Rather than have PageSentry test the server and report an error, a schedule can be created so that tests are not run during scheduled backups.

Click the "Set Schedule" button to open the schedule dialog box. The box includes a grid of squares, each of which represents one hour of an entire week. Red squares signify periods when PageSentry will perform the Sentry tests, and grey areas denote periods when testing will be suspended. Click and drag the mouse to set the schedule needed.

Notification Setup

At the bottom of the Edit Sentry window is the "Notification Setup" area. A list of available Notifiers will be shown on the left of this section. To add a Notifier to a Sentry, simply select it and click "Add". Likewise, select a Sentry from "Notifiers to Execute" and click "Remove" to remove the Notifier from the Sentry. Selecting a Notifier and clicking "Edit" causes the Notifier Editor window to open for the selected Notifier.

Sentry Types

In addition to these common fields, each Sentry will need more information relating to the type of server being monitored.

There are 14 Sentry types, as listed below:

HTTP Sentry	For monitoring Web servers
SMTP Sentry	For monitoring E-Mail servers
FTP Sentry	For monitoring FTP servers
Telnet Sentry	For monitoring any device that supports Telnet connections, such as Unix servers, routers, etc.
DNS Sentry	For monitoring Domain Name Service servers
AppleShare Sentry	For monitoring AppleShare file servers
TCP Stream Sentry	For monitoring any device that supports TCP at the stream level; used to monitor virtually any type of server, such as NNTP
Ping Sentry	For sending a simple ping to insure that TCP/IP is active on the target device
Pulse	For monitoring PageSentry itself, and periodic status reports
Connection	For any TCP/IP server
AppleEvent	For writing your own test types in AppleScript
POP	For monitoring POP mail servers
IMAP	For monitoring IMAP mail servers
Process Watch	For monitoring any application on any Macintosh

Copyright © 1995-2002 Maxum Development Corporation http://www.maxum.com/ Rev. 7/10/02	Previous | Next Contents