PRTG Manual: Scheduling Network Discoveries
While you can always run network discoveries manually, it can also be convenient to have UVexplorer run discoveries for you automatically on a scheduled basis. For example, you could schedule a discovery to run every day at 2:00 PM. Scheduled discoveries allow you to capture the state of your network at regular intervals. Not only does this automatically keep your discovery results up-to-date, but it also allows you to have a record of how your network is changing over time, and to receive notifications of how things are changing. For example, you might want to be notified each time an unknown device attaches to your network. By running scheduled discoveries, UVexplorer can compare the latest discovery result with previous ones to detect when new devices come onto your network. In general, UVexplorer can notify you when devices enter or leave your network, as well as when network links between devices are added or removed. This information can be invaluable for helping you know what is happening on your network.
NOTE: UVexplorer must be running in order for scheduled discoveries to run. If you exit from the program, scheduled discoveries will no longer run. UVexplorer is a Windows tray application, and you can Hide the program while allowing it to still run. When it is hidden, UVexplorer will continue to run scheduled discoveries. However, if you exit entirely from the program, scheduled discoveries will not run.
UVexplorer stores two types of discovery results for each scheduled discovery.
Each time a scheduled discovery runs, UVexplorer stores the raw result of the discovery. The raw result stores a snapshot of what the network looked like at the time the scheduled discovery ran. There are multiple raw results for the scheduled discovery in the database, one for each execution of the discovery.
UVexplorer also stores a ‘rollup’ discovery result for each scheduled discovery. Unlike raw discovery results, of which there is one for each execution of the scheduled discovery, there is only one rollup result for each scheduled discovery. The rollup discovery result is the union of all devices that have been seen recently on the network. This includes devices that were seen during the last several executions of the scheduled discovery. The rollup discovery result is useful because networks are dynamic with devices coming and going all the time. While a given scheduled discovery execution might miss some devices because they happened to be off the network when the discovery ran, combining all devices from several recent scheduled discovery runs gives a more accurate picture of the network.
One of the advantages of using scheduled discoveries is the ability it provides to determine how your network is changing over time. Each time a schedule discovery runs, it compares the current state of the network with the prior state of the network to determine what devices have been added and removed, as well as what network links have been added and removed. When changes in the network are detected, UVexplorer generates events to notify you of the changes. Specifically, the following types of events are generated:
Device Added
A new device was detected on the network. This type of event applies to all devices.
A previously known device disappeared from the network. This event is generated only for ‘core’ infrastructure devices such as routers, switches, wireless access points, servers, etc. It is not generated for ‘dynamic’ devices that come and go from the network on a regular basis.
A new network link was added to the network.
A previously known network link disappeared from the network.
Events are displayed in the Events tab of the main UVexplorer window. Optionally, events are also emailed to one or more specified email addresses.
Managing Scheduled Discoveries
To manage your scheduled discoveries, click the Scheduled Discoveries icon on the Home toolbar. This will display the Scheduled Discoveries form. This form allows you to add, configure, delete, and view the status of scheduled discoveries. A list of all existing scheduled discoveries is displayed on the left side of the form. The right side of the form displays a tab view which can be used to view and edit the properties of the currently-selected scheduled discovery.
NOTE: Changes made in the Scheduled Discovery form do not take effect until the form is closed. For example, if you disable a scheduled discovery or change the scheduled on which it runs, these changes will not take effect until the Scheduled Discovery form is closed.
To create a new scheduled discovery, click on the Add icon (the plus sign) just above the scheduled discovery list on the left side of the form. Alternatively, you can right-click anywhere in the scheduled discovery list, and select Add from the context menu. This will cause a new scheduled discovery with the name ‘ScheduledDiscovery’ to be created and selected. You can then edit the properties of the new scheduled discovery in the tab view on the right side of the form.
Configuring a Scheduled Discovery
The properties of a scheduled discovery can be modified by first selecting it in the list of scheduled discoveries. After it has been selected, the tab view on the right side displays the various properties that can be edited.
The Settings tab displays the following scheduled discovery properties:
Name
This is the scheduled discovery’s name. This value must not be empty.
Enabled
This setting determines whether or not the scheduled discovery is enabled. If the scheduled discovery is enabled, it will run according to its specified schedule. When not enabled the scheduled discovery will not run automatically (but may still be run manually).
Discovery Settings
The Discovery Settings drop-down list is used to select the discovery settings that will be used when the scheduled discovery runs. If no discovery settings are selected, the scheduled discovery will not run. The Discovery Settings drop-down list displays all existing discovery settings from which you may choose. If the desired discovery settings do not already exist, you can click the Settings button to bring up the Discovery Settings form, which allows the creation of new discovery settings.
Keep the Last N Discovery Results
A scheduled discovery will run many times, and each execution will create an additional raw discovery result. Over time, many raw discovery results will accumulate. Typically, it is only useful to keep a relatively small number of the most recent discovery results. This setting lets you specify how many of the most recent raw discovery results to keep. All raw discovery results beyond the specified number will be automatically deleted.
Remember Dynamic Devices for N (Days, Hours, Minutes)
A scheduled discovery’s rollup discovery result contains all devices that have been seen in the several most recent executions of the scheduled discovery. The rollup result contains the set of all ‘known’ devices on the network. When a device has not been seen for multiple consecutive discoveries, it is necessary to eventually drop the device from the rollup discovery result, at which point the device becomes ‘unknown’ again. This setting lets you specify how long to wait before dropping a device from the rollup discovery result. Once a device has been dropped, if it is ever seen again in a future discovery run, it will generate a ‘device added’ event.
The Schedule tab lets you specify the schedule on which the discovery should run. The following schedule types are available:
Minutes
This schedule will run the discovery every N minutes. For example, ‘Run every 30 minutes’.
Hours
This schedule will run the discovery every N hours at a specified minute during the hour. For example, ‘Run every 6 hours’.
Days
This schedule will run the discovery every N days at a specified time of day. For example, ‘Run every 3 days at 2:00 PM’.
Weekly
This schedule will run the discovery weekly on specified days of the week at a specified time of day. For example, ‘Run every Friday at 2:00 PM’.
Monthly (Nth day of month)
This schedule will run the discovery monthly on the Nth day of the month at a specified time of day. For example, ‘Run on the 1st day of each month at 2:00 PM’.
Monthly (Ordinal day of week)
This schedule will run the discovery monthly on the first, second, third, fourth, or last occurrence of the specified week day. You can also specify the time of day at which the discovery will run. For example, ‘Run the last Friday of each month at 2:00 PM’.
The Events tab lets you specify how scheduled discovery events will be reported.
Log Events
This setting controls whether or not scheduled discovery events are displayed in the UVexplorer Events tab.
Display System Tray Notifications on Logged Events
This setting controls whether or not a system tray (i.e., balloon) notification is displayed to alert you about new scheduled discovery events.
Send Email Notification Containing Events
This setting controls whether or not a notification email is sent each time the scheduled discovery completes. The email contains a summary of the scheduled discovery results, including all network changes that were detected. If this setting is checked, email notifications will be sent to all email addresses specified in the Recipient Addresses field.
Recipient Addresses
A list of email addresses to which scheduled discovery email notifications will be sent. If multiple addresses are specified, they should be separated with commas or semicolons.
Include System Recipients
If this option is checked, email notifications will also be sent to all email addresses specified in the Recipient Addresses field of the global email settings. (To view the global email settings, go to the main UVexplorer window, select the Settings toolbar, and click the Email Settings icon.)
When the PRTG connector is available UVexplorer can export to PRTG at the conclusion of a scheduled discovery. See Export to PRTG for more information.
Viewing a Scheduled Discovery’s Status
The status of a scheduled discovery can be viewed by first selecting it in the list of scheduled discoveries, and then selecting the Status tab on the right side. The following information is displayed:
Current State
This field displays the current state of the scheduled discovery. The possible values for this field are as follows:
1.Created: The scheduled discovery was created, but has never run.
2.Running: The scheduled discovery is currently running.
3.Complete: The scheduled discovery is not currently running, and it successfully completed the last time it ran.
4.Canceled: The scheduled discovery is not currently running, and it was canceled the last time it ran.
5.TimedOut: The scheduled discovery is not currently running, and it timed out the last time it ran.
6.Faulted: The scheduled discovery is not currently running, and it encountered an error the last time it ran.
Last Start Time
This field displays the date and time at which the scheduled discovery last started. This will be empty if the scheduled discovery has never run.
Last End Time
This field displays the date and time at which the scheduled discovery last ended. This will be empty if the scheduled discovery has never run, or if it is currently running.
Manually Running a Scheduled Discovery
A scheduled discovery can be manually executed on demand by first selecting it in the list of scheduled discoveries, and then selecting the Status tab on the right side. The following operations are available:
Run Now
This button is enabled only if the scheduled discovery is not already running. Clicking it will start the scheduled discovery. It might take several seconds for the discovery to begin.
Stop
This button is enabled only if the scheduled discovery is currently running. Clicking it will cancel the scheduled discovery. It might take several seconds for the discovery to stop.
Tasks
This button is enabled only if the scheduled discovery is currently running. Clicking it will display the Discovery Tasks form. This form displays detailed information about what the scheduled discovery is currently doing. It is useful for determining what devices are currently being discovered, what information is being collected from these devices, and why the discovery has not yet completed. It also allows discovery sub-tasks to be individually canceled. This can be useful if for some reason discovery gets stuck on a badly-behaving device.
Deleting a Scheduled Discovery
To delete an existing scheduled discovery, select it in the scheduled discovery list on the left side of the form, and then click the Delete icon (with the red X) just above the list. Alternatively, you can right-click on the scheduled discovery in the list, and select Delete from the context menu. The deleted scheduled discovery should disappear from the list.
