PRTG Manual: HTTP Transaction Sensor
The HTTP Transaction sensor monitors an interactive website, such as a web shop, by performing a transaction using a set of HTTP URLs. The sensor monitors whether logins or shopping carts work properly.
The sensor can show the following:
- Loading time of single URLs
- Loading time of the complete transaction
- Dutch: HTTP (Transactie)
- French: Transaction HTTP
- German: HTTP (Transaktion)
- Japanese: HTTP トランザクション
- Portuguese: Transação HTTP
- Russian: Транзакция HTTP
- Simplified Chinese: HTTP 处理
- Spanish: HTTP Transacción
- This sensor does not support Secure Remote Password (SRP) ciphers. If you need to use SRP ciphers, use the Alternate/Compatibility Mode in the sensor settings.
- This sensor supports smart URL replacement.
- This sensor supports the IPv6 protocol.
- This sensor has a high performance impact.
- See the Knowledge Base: Configuration Tips for HTTP Transaction Sensors needed
- See the Knowledge Base: Which user agent should I use in the HTTP Advanced sensor's settings?
The Add Sensor dialog appears when you manually add a new sensor to a device. It only shows the setting fields that are required for creating the sensor. Therefore, you do not see all setting fields in this dialog. You can change (nearly) all settings in the sensor's Settings tab later.
Click the Settings tab of a sensor to change its settings.
Usually, a sensor connects to the IP Address or DNS Name of the parent device on which you created the sensor. See the device settings for details. For some sensors, you can explicitly define the monitoring target in the sensor settings. See below for details on available settings.
Setting |
Description |
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Sensor Name |
Enter a meaningful name to identify the sensor. By default, PRTG shows this name in the device tree, as well as in alarms, logs, notifications, reports, maps, libraries, and tickets.
|
Parent Tags |
Shows tags that the sensor inherits from its parent device, parent group, and parent probe. This setting is shown for your information only and cannot be changed here. |
Tags |
Enter one or more tags. Confirm each tag with the Spacebar key, a comma, or the Enter key. You can use tags to group objects and use tag-filtered views later on. Tags are not case-sensitive. Tags are automatically inherited.
The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:
|
Priority |
Select a priority for the sensor. This setting determines the position of the sensor in lists. The highest priority is at the top of a list. Choose from the lowest priority ( |
Setting |
Description |
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Timeout (Sec.) |
Enter a timeout in seconds for all HTTP requests. If the complete transaction takes longer than this value, the sensor cancels the request and shows an according error message. Enter an integer value. The maximum value is 900 seconds (15 minutes). |
Single URL Timeout (Sec.) |
Enter a timeout in seconds for one single HTTP request. If the reply of any single request takes longer than this value, the sensor cancels the transaction and shows an according error message. Enter an integer value. The maximum value is 900 seconds (15 minutes). |
Setting |
Description |
---|---|
Monitoring Engine |
If you encounter unexpected errors with the standard method that is used to monitor a URL, try the compatibility mode, which is based on .NET. Choose between:
|
SSL/TLS Specific (when using Compatibility Mode)
Setting |
Description |
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SSL/TLS Method |
When using the compatibility mode, the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) specific settings are a bit different from the default SSL/TLS settings. You can choose from:
|
Check SSL Certificates |
Specify if the sensor checks the certificate of the URL:
|
This sensor implicitly supports SNI, an extension to the Transport Layer Security (TLS) protocol.
Setting |
Description |
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Download Limit (KB) |
Enter a number that defines the maximum amount of data (in kilobytes) that is transferred per request.
|
Cookie Management |
Select if cookies are used for the transaction:
|
User Agent |
Select the user agent string that the sensor sends when connecting to the URLs:
|
Custom User Agent |
This setting is only visible if you enable Use a custom string above. Enter a string that the sensor uses as the user agent when connecting to the URL. |
Result Handling |
Define what PRTG does with the web page that is loaded at the URL:
|
Setting |
Description |
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Authentication |
Define if authentication is necessary on the web page at the configured URL:
|
User |
This setting is only visible if you enable Web page needs authentication above. Enter a username. Enter a string. |
Password |
This setting is only visible if you enable Web page needs authentication above. Enter a password. Enter a string. |
Authentication Method |
This setting is only visible if you enable Web page needs authentication above. Select the authentication method that the URL is protected with:
|
You can define up to 10 different transaction URLs, which are all called in a row. If the transaction can be completed, the sensor shows the Up status. Using this mechanism, you can set up extended monitoring with multiple URLs.
Enter settings for at least one transaction URL. You can use as many steps as needed and disable the other steps.
Setting |
Description |
---|---|
Transaction Step #x |
This setting is available for URL #2 through #10. Define if you want to use this step for your transaction check:
|
URL |
Enter the URL that the sensor connects to.
If you enter an absolute URL, this address is independent of the IP Address/DNS Name setting of the parent device. PRTG uses a smart URL replacement that lets you use the parent device's IP address/DNS name setting as part of the URL.
|
Request Method |
Define how the URL is requested:
|
Postdata |
This setting is only active if you choose POST in the Request Method setting above. Enter the data part for the post request here.
|
Require Keyword |
Define if the sensor checks the result at the URL for keywords:
|
Response Must Include |
Define a string that must be part of the result at the URL. If the data does not include this string, the sensor shows the Down status and displays this string along with the affected URL in the sensor message. Enter a string.
|
Exclude Keyword |
Define if the sensor checks the result at the URL for keywords:
|
Response Must Not Include |
Define a string that must not be part of the result at the URL. If the data includes this string, the sensor shows the Down status and displays this string along with the affected URL in the sensor message. Enter a string.
|
Setting |
Description |
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Primary Channel |
Select a channel from the list to define it as the primary channel. In the device tree, the last value of the primary channel is always displayed below the sensor's name. The available options depend on what channels are available for this sensor.
|
Graph Type |
Define how different channels are shown for this sensor:
|
Stack Unit |
This setting is only visible if you enable Stack channels on top of each other as Graph Type. Select a unit from the list. All channels with this unit are stacked on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so. |
By default, all of the following settings are inherited from objects that are higher in the hierarchy. You should change them centrally in the root group settings if necessary. To change a setting for this object only, click under the corresponding setting name to disable the inheritance. You then see the options described below.
For more information, see section Inheritance of Settings.
Proxy Settings for HTTP Sensors
Click to interrupt the inheritance.
The proxy settings determine how a sensor connects to a URL. You can enter data for an HTTP proxy server that sensors use when they connect via HTTP or HTTPS.
This setting only applies to HTTP sensors and how they monitor. To change the proxy settings for the PRTG core server, see section Core & Probes.
Setting |
Description |
---|---|
Name |
Enter the IP address or Domain Name System (DNS) name of the proxy server. If you leave this field empty, HTTP sensors do not use a proxy. |
Port |
Enter the port number of the proxy. The default is 8080. Enter an integer value. |
User |
If the proxy requires authentication, enter the username for the proxy login.
|
Password |
If the proxy requires authentication, enter the password for the proxy login.
|
Click to interrupt the inheritance.
Setting |
Description |
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Scanning Interval |
Select a scanning interval from the dropdown list. The scanning interval determines the amount of time that the sensor waits between two scans. Choose from:
|
If a Sensor Query Fails |
Select the number of scanning intervals that the sensor has time to reach and to check a device again if a sensor query fails. Depending on the option that you select, the sensor can try to reach and to check a device again several times before the sensor shows the Down status. This can avoid false alarms if the monitored device only has temporary issues. For previous scanning intervals with failed requests, the sensor shows the Warning status. Choose from:
|
Schedules, Dependencies, and Maintenance Window
You cannot interrupt the inheritance for schedules, dependencies, and maintenance windows. The corresponding settings from the parent objects are always active. However, you can define additional schedules, dependencies, and maintenance windows. They are active at the same time as the parent objects' settings.
Setting |
Description |
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Schedule |
Select a schedule from the list. You can use schedules to monitor during a certain time span (days or hours) every week. Choose from:
|
Maintenance Window |
Select if you want to set up a one-time maintenance window. During a maintenance window, monitoring stops for the selected object and all child objects. They show the Paused status instead. Choose between:
|
Maintenance Begins |
This setting is only visible if you enable Set up a one-time maintenance window above. Use the date time picker to enter the start date and time of the one-time maintenance window. |
Maintenance Ends |
This setting is only visible if you enable Set up a one-time maintenance window above. Use the date time picker to enter the end date and time of the one-time maintenance window. |
Dependency Type |
Select a dependency type. You can use dependencies to pause monitoring for an object depending on the status of a different object. You can choose from:
|
Dependency |
This setting is only visible if you enable Select a sensor above. Click |
Dependency Delay (Sec.) |
This setting is only visible if you enable Select a sensor above. Define a time span in seconds for the dependency delay. After the master sensor for this dependency returns to the Up status, PRTG additionally delays the monitoring of the dependent objects by the time span you define. This can prevent false alarms, for example, after a server restart or to give systems more time for all services to start. Enter an integer value.
|
Click to interrupt the inheritance.
Setting |
Description |
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User Group Access |
Define the user groups that have access to the sensor. You see a table with user groups and group access rights. The table contains all user groups in your setup. For each user group, you can choose from the following group access rights:
|
Instead of entering a complete address in the URL field of an HTTP sensor, you can only enter the protocol followed by a colon and three forward slashes (this means that you can enter either http:/// or https:///, or even a simple forward slash / as the equivalent for http:///). PRTG automatically fills in the parent device's IP address or DNS name in front of the third forward slash.
Whether this results in a valid URL or not depends on the IP address or Domain Name System (DNS) name of the parent device. In combination with cloning devices, you can use smart URL replacement to create many similar devices.
For example, if you create a device with the DNS name www.example.com and you add an HTTP sensor to it, you can provide values in the following ways:
- If you enter https:/// in the URL field, PRTG automatically creates the URL https://www.example.com/
- If you enter /help in the URL field, PRTG automatically creates and monitor the URL http://www.example.com/help
- It is also possible to provide a port number in the URL field. It is taken over by the device's DNS name and is internally added, for example, http://:8080/
Smart URL replacement does not work for sensors that run on the probe device.
PRTG MANUAL
KNOWLEDGE BASE
Configuration Tips for HTTP Transaction Sensors needed
My HTTP sensors don't work. What can I do?
For more information about sensor settings, see the following sections: