<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: IMAP Sensor

Sensor Name

Enter a meaningful name to identify the sensor. By default, PRTG shows this name in the device tree, and in alarms, logs, notifications, reports, maps, libraries, and tickets.

Tags

Enter one or more tags, separated by space or comma. You can use tags to group sensors and use tag-filtered views later on. Tags are not case sensitive. We recommend using the default value. You can add additional tags to it, if you like. Other tags are automatically inherited from objects further up in the device tree. Those are not visible here.

Priority

Select a priority for the sensor. This setting determines where the sensor is placed in sensor lists. Top priority is at the top of a list. You can choose from one star (low priority) to five stars (top priority).

Timeout (Sec.)

Enter a timeout in seconds for the request. If the reply takes longer than this value defines, the sensor will cancel the request and show a corresponding error message. Please enter an integer value. The maximum value is 900 seconds (15 minutes).

Port

Enter the number of the port that the sensor uses to connect via IMAP. For non-secure connections, usually port 143 is used. For SSL connections it is usually port 993. The actual setting depends on the server you are connecting to. Please enter an integer value. We recommend using the default value.

If you do not get a connection, please try another port number.

Username

Enter a username for IMAP authentication. Please enter a string.

Password

Enter a password for IMAP authentication. Please enter a string.

Sensor Specific

Define the security level for the sensor connection. Choose between:

• Use Transport-Level Security if available using StartTLS (default): Choose this option to try connecting to the server using TLS and StartTLS. If the server does not support this, the sensor will try connecting without encryption.
• Use Transport-Level Security if available: Choose this option to try connecting to the server using TLS. If the server does not support this, the sensor will try connecting without encryption.
• Enforce Transport-Level Security using StartTLS: Choose this option to try connecting to the server using TLS and StartTLS. If the server does not support this, the sensor will show a Down status.
• Enforce Transport-Level Security: Choose this option to try connecting to the server using TLS. If the server does not support this, the sensor will show a Down status.

If the sensor connects to a server via StartTLS, the connection is established unencrypted first. After the connection is established, the sensor sends a certain command (StartTLS) over the unencrypted connection to negotiate a secure connection via the SSL/TLS protocol.

If the sensor uses TLS without StartTLS, the negotiation of a secure connection happens immediately (implicitly) so that no commands are sent in unencrypted plain text. If there is no secure connection possible, no communication will take place.

Process Email Content

This sensor can additionally check the content of all incoming emails. Choose between:

• Do not check email content: Only check availability of the IMAP server and check if a login is successful (if defined). Do not process any emails in the IMAP email account.
• Read email count: Count the emails in the defined mailbox.

• Process emails in this mailbox: Login in to the IMAP email account and check the emails which it contains. Define further options below.

Mailbox Name

This field is only visible if you enable email counting or content processing above. Enter the name of the mailbox (for example, the name of the IMAP folder) that the sensor checks. Default value is Inbox. Unless you set a last message date check below, the sensor will always look at all emails contained in the mailbox.

Note: Ensure you do not manually edit emails in this mailbox with another email client because this can result in malfunctions of this sensor's email identification.

Identify by "From" Field

This option is only visible if you enable email content processing above. Define if you want to check the "From" field of the emails. Choose between:

• Don't check: Do not process this field in emails.
• Check using string search: Process this field in emails using simple string search.
• Check using regular expression: Process this field in emails using a regular expression. For more information about syntax, please see Regular Expressions section.

When using a search, the sensor will scan all emails from the newest to the oldest.

Note: The sensor finishes the scan with the first match! This means that after it finds a match in one email, there will be no further checks performed in older emails.

Search For

This field is only visible if you enable a "from" check above. Enter a search string using the method defined above.

Identify by "Subject" Field

This option is only visible if you enable content processing above. Define if you want to check the "Subject" field of the emails. Choose between:

• Don't check: Do not check this field in emails.
• Check using string search: Check this field in emails using simple string search.
• Check using regular expression: Check this field in emails using a regular expression. For more information about syntax, please see Regular Expressions section.

When using a search, the sensor will scan all emails from the newest to the oldest.

Note: The sensor finishes the scan with the first match! This means that after it finds a match in one email, there will be no further checks performed in older emails.

Search For

This field is only visible if you enable a "subject" check above. Enter a search string using the method defined above.

Identify by Mail Body

This option is only visible if you enable content processing above. Define if you want to check the mail body of the emails. Choose between:

• Don't check: Do not check the mail body.
• Check using string search: Check the mail body using simple string search.
• Check using regular expression: Check the mail body using a regular expression. For more information about syntax, please see Regular Expressions section.

When using a search, the sensor will scan all emails from the newest to the oldest.

Note: The sensor finishes the scan with the first match! This means that after it finds a match in one email, there will be no further checks performed in older emails.

Search For

This field is only visible if you enable checking the mail body above. Enter a search string using the method defined above.

Check Last Message Date

This option is only visible if you enable content processing above. Define if you want to check all emails in the mailbox, or only mails that were received within the last x hours. Choose between:

• Don't check message age: Always check all emails contained in the mailbox.
• Check for new messages received within the last x hours: Only regard emails that were received in the last hours. Define below.

Error Threshold (Hours)

Enter the maximum age in hours. The sensor processes only emails that are younger. If there is no matching email in the defined time span, the sensor will show a Down status.

Warning Threshold (Hours)

Enter the maximum age in hours. The sensor processes only emails that are younger. If there is no matching email in the defined time span, the sensor will show a Warning status.

Set to Error

This setting is only visible if you enable email content check above. Define in which cases the sensor will show a Down status. Choose between:

• Never (default): Never set this sensor to a Down status based on email content.
• Always: Always set this sensor to a Down status in case any emails could be identified.
• If subject contains
• If subject does not contain
• If mail body contains
• If mail body does not contain

Check Method

This setting is only visible if you select an if-condition above. Define how you want to check for the above condition. Choose between:

• String search: Check the mail body using simple string search.
• Regular expression: Check the mail body using a regular expression. For more information about syntax, please see Regular Expressions section.

When using a search, the sensor will scan all emails from the newest to the oldest.

Note: The sensor finished the scan with the first match! This means that after it finds a match in one email, there will be no further checks performed in older emails.

Search Text

This setting is only visible if you select an if-condition above. Enter a search string using the method defined above.

Error Message

This setting is only visible if you select an alarm condition above. Define the message that the sensor will show for a Down status.

Set to Warning

This setting is only visible if you enable content check above. Define in which cases the sensor will show a Warning status. Choose between:

• Never (default): Never set this sensor to a Warning status based on email content.
• Always: Always set this sensor to a Warning status in case any emails could be identified.
• If subject contains
• If subject does not contain
• If mail body contains
• If mail body does not contain

Check Method

This setting is only visible if you select an if-condition above. Define how you want to check for the above condition. Choose between:

• String search: Check the mail body using simple string search.
• Regular expression: Check the mail body using a regular expression. For more information about syntax, please see Regular Expressions section.

When using a search, the sensor will scan all emails from the newest to the oldest.

Note: The sensor finishes the scan with the first match! This means that after it finds a match in one email, there will be no further checks performed in older emails.

Search Text

This setting is only visible if you enable an if-condition above. Enter a search string using the method defined above.

Warning Message

This setting is only visible if you select a warning condition above. Define the message that the sensor will show for a Warning status.

No Matching Mail Behavior

This setting is only visible if you enable content check above. Define how the sensor will react if it does not find matching emails in the mailbox that it scans. Choose between:

• Set sensor to "Down" status
• Set sensor to "Warning" status
• None: Do not do anything in this case.

Message

This field is only visible if you enable a no matching behavior above. Define the message that the sensor will show if it did not find any matching emails together with a Warning or Down status as you define above.

Sensor Result

Define what PRTG will do with the result of the sensor. Choose between:

• Discard sensor result: Do not store the sensor result.
• Write sensor result to disk (Filename: "Result of Sensor [ID].txt"): Store the last result received from the sensor to the "Logs (Sensor)" directory (on the Master node, if in a cluster). File name: Result of Sensor [ID].txt. This is for debugging purposes. The file will be overridden with each scanning interval. For information on how to find the folder used for storage, please see Data Storage section.

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 will always be displayed underneath the sensor's name. The available options depend on what channels are available for this sensor. Note: You can set another primary channel later by clicking on the pin symbol of a channel in the sensor's overview tab.

Chart Type

Define how different channels will be shown for this sensor.

• Show channels independently (default): Show an own graph for each channel.

• Stack channels on top of each other: Stack channels on top of each other to create a multi-channel graph. This will generate an easy-to-read graph which visualizes the different components of your total traffic. Note: This option cannot be used in combination with manual Vertical Axis Scaling (available in the Sensor Channels Settings settings).

Stack Unit

This setting is only available if stacked graphs are selected above. Choose a unit from the list. All channels with this unit will be 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.

Scanning Interval

Scanning Interval

Select a scanning interval (seconds, minutes, or hours) from the list. The scanning interval determines the time the sensor waits between two scans. You can change the available intervals in the system administration.

When a Sensor Reports an Error

Define the number of scanning intervals a sensor has to report an error until the sensor will be set to a Down status. The sensor can try reaching a device several times, depending on your setup you can specify here, to help avoid false alarms if the monitored device has only temporary issues. For previous scanning intervals with failed requests, the sensor will show a Warning status. Choose between:

• Set sensor to "down" immediately: The sensor will show an error after the first failed request.
• Set sensor to "warning" for 1 interval, then set to "down" (recommended): After the first failed request, the sensor will show a yellow warning status. If the following request also fails, the sensor will show an error.
• Set sensor to "warning" for 2 intervals, then set to "down": Show an error status only after three failed requests in a row.
• Set sensor to "warning" for 3 intervals, then set to "down": Show an error status only after four failed requests in a row.
• Set sensor to "warning" for 4 intervals, then set to "down": Show an error status only after five failed requests in a row.
• Set sensor to "warning" for 5 intervals, then set to "down": Show an error status only after six failed requests in a row.

Note: Sensors that monitor via Windows Management Instrumentation (WMI) always wait at least one scanning interval until they show an error. It is not possible to set a WMI sensor "down" immediately, so the first option will not apply to these sensor types (all other options can apply).

Note: If a sensor has defined error limits for channels, this sensor will always be set to a Down status immediately, so no "wait" option will apply.

Note: If a channel uses lookup values, the sensor will always be set to a Down status immediately, so no "wait" options will apply.

Note: Inheritance for schedules, dependencies, and maintenance windows cannot be interrupted; the according settings from the parent objects will always be active. However, you can define additional settings here. They will be active in parallel to the parent objects' settings.

Schedule

Select a schedule from the list. Schedules can be used to monitor for a certain time span (days, hours) throughout the week. With the period list option it is also possible to pause monitoring for a specific time span. You can create new schedules and edit existing ones in the account settings.

Note: Schedules are generally inherited. New schedules will be added to existing ones, so all schedules are active.

Maintenance Window

Specify if you want to set-up a one-time maintenance window. During a maintenance window this object and all child objects will not be monitored. They will enter a paused state then. Choose between:

• Not set (monitor continuously): No maintenance window will be set.
• Set up a one-time maintenance window: Pause monitoring within a maintenance window. You can define a time span for a monitoring pause below and change it even for a running maintenance window.

Note: To terminate a current maintenance window before the defined end date, you can change the time in Maintenance End At field to a date in the past.

Maintenance Begins At

This field is only visible if maintenance window is enabled above. Use the date time picker to enter the start date and time of the maintenance window.

Maintenance End At

This field is only visible if maintenance window is enabled above. Use the date time picker to enter the end date and time of the maintenance window.

Dependency Type

Define a dependency type. Dependencies can be used to pause monitoring for an object depending on the status of another. You can choose between:

• Use parent: Pause the current sensor if the device it is created on is in a Down status, or if it is paused by another dependency.
• Select object: Pause the current sensor if the device it is created on is in an Down status, or if it is paused by another dependency. Additionally, pause the current sensor if a specific other object in the device tree is in a Down status, or if it is paused by another dependency. Select below.
• Master object for parent: Make this sensor the master object for its parent device. The sensor will influence the behavior of the device it is created on: If the sensor is in a Down status, the device will be paused. For example, it is a good idea to make a Ping sensor the master object for its parent device to pause monitoring for all other sensors on the device in case the device cannot even be pinged. Additionally, the sensor will be paused if the parent group of its parent device is in a Down status, or if it is paused by another dependency.

Note: Testing your dependencies is easy! Simply choose Simulate Error Status from the context menu of an object that other objects depend on. A few seconds later all dependent objects should be paused. You can check all dependencies in your PRTG installation by selecting Devices | Dependencies from the main menu bar.

Dependency

This field is only visible if the select object option is enabled above. Click on the reading-glass symbol and use the object selector to choose an object on which the current sensor will be dependent on.

Delay (Seconds)

Define a time span. After the master object for this dependency comes back to an Up status, monitoring of the depending objects will be additionally delayed by the defined time span. This can help avoid false alarms, for example, after a server restart, by giving systems more time for all services to start up. Please enter an integer value in seconds. Note: This setting is not available if you choose this sensor to be the Master object for parent. In this case, please define delays in the parent Device Settings or the superior Group Settings.

Access Rights

User Group Access

Define which user group(s) will have access to the object you're editing. A table with user groups and right is shown; it contains all user groups from your setup. For each user group you can choose from the following access rights:

• Inherited: Use the settings of the parent object.
• None: Users in this group cannot see or edit the object. The object does not show up in lists and in the device tree. Exception: If a child object is visible to the user, the object is visible in the device tree, though not accessible.
• Read: Users in this group can see the object and review its monitoring results.
• Write: Users in this group can see the object, review its monitoring results, and edit the object's settings. They cannot edit access rights settings.
• Full: Users in this group can see the object, review its monitoring results, edit the object's settings, and edit access rights settings.

You can create new user groups in the System Administration—User Groups settings. To automatically set all objects further down in the hierarchy to inherit this object's access rights, set a check mark for the Revert children's access rights to inherited option.

For more details about access rights, please see section User Access Rights.