Web Interface
The AJAX-based web interface is used for the configuration of devices and sensors, as well as the review of monitoring results. The web interface is highly interactive and uses AJAX ("Asynchronous Javascript and XML") to deliver a powerful and easy-to-use user experience. While the user is logged in, the data on the screen is permanently refreshed (via Ajax calls) so it always shows the current monitoring results (refresh interval and method can be set by the user).
Login
As default, login name and password are both "prtgadmin" (without the quotes), unless specified differently during setup. You can change login name and password any time using PRTG Server Administrator.
The Interface
After logging into the web interface, you will see PRTG's welcome page as default. This page helps you to add sensors manually, perform an automatic network search, review results, download the Windows-GUI or iPhone applications and get further help and support.

By clicking on "Review Results", you enter the tree-like device view which will be your starting point for everyday use. Please have a look at this screenshot of PRTG's device page in the web interface:

The main layout consists of a status bar at the top, the header area with the main menu and quick-search box below it and, finally, the main page content (all these elements are described in the next section).
When you navigate through PRTG's web interface you will always use one of the following five navigational paths:
- The main menu provides access to all important aspects of the software.
- The quick search is often the fastest way to navigate to an object.
- Using the page's tabs, you can switch between various sub-pages for an object.
- Many objects offer a context menu that will pop up when you right-click them.
- And, finally, you are able to drill down into the object hierarchy of probes, groups, devices and sensors in the object tree shown above by merely clicking an sub-object of the currently displayed object (e.g. a sensor on the device page).
These five navigation paths put PRTG's complete functionality at your fingertips. Quite likely you are already familiar with these techniques from many other websites and web-based user interfaces.
Let's have a detailed look at PRTG's web interface -building blocks:
Global Status Bar and Sensor Colors
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This bar is always shown above all pages. It shows the aggregated status of all sensors you have configured for monitoring. Depending on the sensors' status you will see colored squares with numbers which symbolize the sensors (in the screenshot above, 23 sensors are red, 3 are yellow, 95 sensors are green, 129 sensors are blue and 40 are orange).
The color of a sensor always shows it's current status:
Sensor Status |
Meaning |
|
|
Red |
Down |
|
Red (confirmed) |
Down - this status is additionally verified |
|
Yellow |
Warning |
|
Green |
OK |
|
Blue |
Paused |
|
Orange |
Unusual |
|
Black |
Unknown (sensor has not been checked yet) |
Unusual status: If this setting is enabled for a sensor or a whole group, a sensor will be set to an "unusual" state if its current readings differ in their values more than expected, compared to the readings stored in the past.
The four graphs in the global status bar show the number of alarms as well as three "Index" graphs for response time, CPU load and bandwidth traffic usage over the last 24 hours. These graphs are "index" graphs, similar to a stock index. The values are based on the readings of all sensors, groups or devices. They are computed by using statistical computations and by comparing the values to the highest and lowest readings ever recorded. For example, a CPU Load Index value of 90 % means that the average CPU load for all CPU sensors of your current configuration lies at 90 % of the highest ever measured CPU usage value.
Website Header Area, Search Box and Main Menu
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Navigating through the web interface is performed using the main menu. Please take a few minutes to familiarize yourself with all menu items and sub-items. Menu item "Alarms" is highlighted with red color whenever there is an alarm. "Logs" and "ToDos" are highlighted with blue color if new messages or new ToDos are available. To search for any monitoring object, simply enter the name, part of the name, an IP address, a DNS name or a tag in the search box on the right and hit the enter key. A web page with all items that fit the search term will be returned - even displaying online help articles.
Page Header and Tabs

The individual page content starts below the website header area. Depending on the page's content you will see a menu and a few action links on the right. "Breadcrumbs" that will always show the path back to the homepage can be found below the heading. The yellow boxes display context sensitive help which can be hidden by clicking the small "x" on the top right.
Many pages have a tab-like interface. Using these tabs you can navigate to various sub-pages for an object:
Tab(s) |
Description |
"Overview" |
All monitoring objects offer this tab providing a quick overview of all parameters and statuses. |
"Live Data", "48 Hours", "30 Days", "365 Days" |
These three or four tabs show the group's, device's or sensor's historical graphs and data tables (note: live data is only available for sensors). |
"Historic Data" |
With this function, you can review or download historic sensor data. See below for further explanations ("Reviewing Historic Data"). |
"Alarms" and "Log" |
Shows a list of current alarms and historic events for an object (and its child objects). |
"Settings" and "Notifications" |
Allows you to edit an object's settings and notifications. The available settings depend on the kind of object you are editing. |
"Channels" |
This tab is only available for sensors. Each sensor has one or more channels on which it stores data. In this tab, you can configure how a channel's values are processed. See section Edit Sensor and Channel Settings for more details. |
"Comments" |
Provides a notepad for your own comments. |
"History" |
Shows a lifetime log for each object (who created it, who edited it etc.). |
These are the most common tabs. Please note that you will also see other tabs for other objects.
If you make any changes in a tab, please make sure you click on the "Save" button to save your changes. If you change tabs without saving, your changes will be discarded.
Overview Page for Groups, Devices and Sensors
Have a look at the following three screenshots showing the "Overview" tab of a group, a device and a sensor:

You can see that all three share a common layout:
- On the upper left you have the object's name, basic settings and sensor status.
- Below that there is a list of child objects (devices for a group, sensors for a device and channels for a sensor).
- On the right there are three or four graphs showing recent history. To zoom into a graph, simply click on it (or choose the appropriate tab).
For sensors you will see four graphs that show all "channels" of the sensor for the last 2 days, last 30 days and last 365 days plus a live graph. For groups and devices there are three graphs that show the alarms, CPU load index, traffic index and response time index (explained above) for the last 2 days, last 30 days and last 365 days. Details about index calculation are available in the Paessler Knowledge Base at http://www.paessler.com/support/kb/prtg7/how_prtg_computes_index_graphs.
Note: Time frames can be changed in the PRTG Server Administrator ("Memory Usage" tab).
Box with Alerts
Every time a new event occurs while you are logged into the web interface of PRTG Network Monitor a box with alerts will show up in the lower right corner of your browser window:

Please keep an eye on these important messages which PRTG will display as it discovers changes in the network or requires your attention for other reasons. Simply click the text inside the colored bar to navigate to the detailed information page or click one of the "x" symbols to dismiss and hide the alert. In the user account settings you can control which events actually display the popup. There, you can also disable this feature.
Context Menus
Although context menus may seem unusual for a web-based application, they are the key to user interface's ease of use. Almost all objects that appear as links in the user interface will show a context menu when your right-click them. Using it, you can access every relevant function of an object. Here are three sample context menus (for group, device and sensor).
Note: If you want to access the browser's own context menu, hold the CTRL key down when right-clicking.
Working with Lists and Multi Edit Menus
Throughout the web interface often you will see lists of items, e.g. sensors, devices, maps, reports etc. All these lists provide common functionality. Here are two sample lists (sensors and logs):


The following functions are available for lists:
Feature |
Display |
What it does |
Paging |
|
Use the small triangular icons at the top or bottom to walk through a list page by page. |
Sorting |
|
You can re-sort a list by clicking the header of the column you want to use as sorting index. |
Date Range |
|
When viewing log lists, you can click on "Date Range" to change the desired date range. |
Item Count |
|
Some lists offer the possibility to change the number of entries in the list by clicking on "Item Count". |
New window |
|
Opens the table in a new window. |
Show XML |
|
Views list as XML (your browser may offer you an XML file download). |
Additionally some lists offer a column of checkboxes. The checkboxes are used to select two or more items from the list and work with the selected items. As soon as you select one or more checkboxes, an additional, green colored menu will show up:

Depending on the object type different functions are available. Some frequently used functions are available as quick buttons, other functions are available in the drop down menu:

Reviewing Historic Data
Additionally to exhaustive reports that additionally can be scheduled for regular execution (see section Reports), you can view a report of the historic data for each single sensor, on demand. Additionally, you can also export this data and download it for further processing in external applications. To get to the Historic Data reports, choose a sensor, right-click on it and from the context menu, select "Details...". In the sensor's detail view, click on the "Historic Data" tab to start the review.

You can select the following options:
- Start: Enter the start date and time of the data you want to review.
- End: Enter the end date and time of the data you want to review.
- Average Interval: With this option, you can activate and set up averaging. Select an interval for which the average value should be calculated. You can choose between "No Interval" (no averaging will be performed), a few seconds, minutes, hours, or a whole day. A smaller interval will result in a more detailed report for this sensor. The best settings for you vary, depending on the Scanning Interval of the sensor, the selected date period and, of course, the intended use for the report. It might be useful to try different settings to see what the results look like.
- File Format: This is the output format for the report. You can select between an HTML web page, an XML file and a CSV file (for import in Microsoft Excel, for example).
- Include Percentiles: Activate this option to add a percentile value to the report. See section Calculating Percentiles for more information.
Click on "Start" to generate the Historic Data report. Please note: Depending on the selected output format, either a new browser window or tab will open and show an HTML web page, or the browser will start the download of an XML or CSV file. If you just generated an HTML web page report and it is still opened while you are generating another, no new browser window or tab will open, but instead the existing HTML web page will be refreshed and it will show the most recent report.
During report calculation PRTG may allocate large amounts of RAM (depending on average interval and the report time span). To avoid system overload and ensure system stability PRTG automatically limits the minimum average interval depending on the time span automatically (selected via Start and End date):
Level of Detail |
Maximum Timeframe in Historic Data Report |
Raw Data (all single monitoring requests) |
For up to 24 hours/1 day |
Averages between 1 and 60 minutes |
For up to 24 hours/1 day |
Averages between 60 and 1440 minutes |
For up to 30 days |
Averages for one or more days |
For up to 365 days/1 year |