<%NUMBERING1%>.<%NUMBERING2%>.<%NUMBERING3%> PRTG Manual: Probe Settings

Probe Name

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

If the name contains angle brackets (<>), PRTG replaces them with braces ({}) for security reasons. For more information, see the Knowledge Base: What security features does PRTG include?

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.

It is not possible to enter tags with a leading plus (+) or minus (-) sign, nor tags with parentheses (()) or angle brackets (<>).

For performance reasons, it can take some minutes until you can filter for new tags that you added.

Status

Select the monitoring status of the probe:

• Started: Monitor the probe.
• Paused: Pause monitoring for the probe. All sensors on all devices on the probe are in the Paused status until you change this setting.

Priority

Select a priority for the probe. This setting determines the position of the probe in lists. The highest priority is at the top of a list. You can choose from the lowest priority () to the highest priority ().

Location (for Geo Maps)

If you want to use Geo Maps, enter a location in the first line. Geographical maps then display objects like devices or groups with a status icon using a color code similar to the sensor status icons (green–yellow–orange–red). You can enter a full postal address, city and country only, or latitude and longitude. It is possible to enter any text before, between, and after the coordinates, as PRTG automatically parses latitude and longitude, for example, enter 49.452778 11.077778, or enter 49.452778 any 11.077778 text.

A minus sign (-) in the first line hides an object from a geographical map. In this case, you can enter location information in line two and following.

You can define a specific label for each location. Enter a string denoting the label in the first line and provide the coordinates in the second line. This geographical marker then shows the object with the label in the geographical map.

The preview map always has a road map layout regardless of the map layout you set in User Interface.

Domain or Computer Name

Enter the domain or computer name of the user account with which you want to access the Windows system. PRTG uses this account for Windows Management Instrumentation (WMI) sensors and other Windows sensors.

If you want to use a Windows local user account on the target device, enter the computer name. If you want to use a Windows domain user account (recommended), enter the domain name. PRTG automatically adds a prefix to use the NT LAN Manager (NTLM) protocol if you do not explicitly define it. Do not leave this field empty.

User Name

Enter the user name for access to the Windows system. Usually, you use credentials with administrator rights.

Password

Enter the password for access to the Windows system. Usually, you use credentials with administrator rights.

User Name

Enter the user name for access to the Linux/Solaris/macOS system via Secure Shell (SSH) and Web-based Enterprise Management (WBEM). Usually, you use credentials with administrator rights.

Authentication Method

Select the authentication method for the login:

• Password: Provide the password for the login.
• Private key: Provide an RSA private key for authentication.

PRTG can only handle keys in the OpenSSH format that are not encrypted. You cannot use password-protected keys.

PRTG only supports RSA keys. It does not support DSA keys.

For details, see section Monitoring via SSH.

Password

This setting is only visible if you select Password above. Enter a password for access to the Linux/Solaris/macOS system via SSH and WBEM. Usually, you use credentials with administrator rights.

Private Key

This setting is only visible if you select Private key above. Paste the entire RSA private key, including the BEGIN and END lines. Make sure that a corresponding public key exists on the target device.

PRTG can only handle keys in the OpenSSH format that are not encrypted. You cannot use password-protected keys.

PRTG only supports RSA keys. It does not support DSA keys.

For details, see section Monitoring via SSH.

If you do not insert a private key for the first time but if you want to change the private key, you need to restart the PRTG core server service for the private key change to take effect.

WBEM Protocol

Select the protocol that you want to use for the connection to the system via WBEM:

• HTTP: Use an unsecure connection for WBEM.
• HTTPS (default): Use a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection for WBEM.

This setting is only relevant if you use WBEM sensors.

WBEM Port

Select if you want to use one of the default ports for the connection to the system via WBEM or if you want to set a custom port:

• Default: Use one of the default ports. The default port for unsecure connections is 5988 and the default port for secure connections is 5989.
• Custom: Use a custom port.

This setting is only relevant if you use WBEM sensors.

Custom WBEM Port

This setting is only visible if you select Custom above. Enter a custom WBEM port. Enter an integer.

SSH Port

Enter the port for SSH connections. Enter an integer. The default port is 22.

By default, PRTG automatically uses this setting for all SSH sensors unless you define a different port number in the sensor settings.

SSH Rights Elevation

Select the rights that you want to use to run the command on the target system:

• Run the command as the connecting user (default): Use the rights of the user who establishes the SSH connection.
• Run the command as a different user using 'sudo' (with password): Use the rights of a different user with a password required for sudo to run commands on the target system, for example, as a root user.
• Run the command as a different user using 'sudo' (without password): Use the rights of a different user without a password required for sudo to run commands on the target system, for example, as a root user.
• Run the command as a different user using 'su': Use the rights of a different user with su to run commands on the target system.

Target System User Name

This setting is only visible if you select an option that includes sudo or su above. Enter a user name to run the specified command on the target system as a different user than the root user. If you leave this field empty, you run the command as a root user. Make sure that you set the Linux password even if you use a public key or a private key for authentication. This is not necessary if the user is allowed to run the command without a password.

Password

This setting is only visible if you select an option that includes sudo or su with password above. Enter the password to run the sudo command or the su command.

SSH Connection Mode

Select the connection mode that you want to use to access data with SSH sensors:

• Default (recommended): This is the default connection mode for SSH sensors. It provides the best performance and security.
• Compatibility mode (deprecated): Use this only if the default connection mode does not work on the target system. The compatibility mode is the connection mode that PRTG used in previous versions and it is deprecated.

We strongly recommend that you use the default connection mode.

You can also individually select the connection mode for each SSH sensor in the sensor settings.

User Name

Enter the user name for access to VMware ESXi, vCenter Server, or Citrix XenServer. Usually, you use credentials with administrator rights.

Password

Enter the password for access to VMware ESXi, vCenter Server, or Citrix XenServer. Usually, you use credentials with administrator rights.

Single sign-on (SSO) passwords for vSphere do not support special characters. For details, see the VMware sensors sections.

VMware Protocol

Select the protocol for the connection to VMware ESXi, vCenter Server, or Citrix XenServer:

• HTTPS (recommended): Use a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection.
• HTTP: Use an unsecure connection.

Session Handling

Select if you want to reuse a session for VMware sensors:

• Reuse a session for multiple scans (recommended): Select this option if you want a VMware sensor to reuse a single session for multiple sensor scans to query data. With this option, the sensor does not need to log in and out for each sensor scan. We recommend that you use this option because it reduces network load and log entries on the target device. This can increase performance.
• Create a new session for each scan: If you select this option, PRTG does not reuse a session and a VMware sensor has to log in and out for each sensor scan. This can decrease performance.

SNMP Version

Select the Simple Network Management Protocol (SNMP) version for the connection to the target SNMP device:

• SNMP v1: Use SNMP v1 for the connection. SNMP v1 only offers clear-text data transmission.
  SNMP v1 does not support 64-bit counters. This might result in invalid data when you monitor traffic via SNMP.
• SNMP v2c (recommended): Use SNMP v2c for the connection. SNMP v2c also only offers clear-text data transmission but it supports 64-bit counters.
• SNMP v3: Use SNMP v3 for the connection. SNMP v3 provides secure authentication and data encryption.
  SNMP v3 has performance limitations because of the use of encryption. The main limiting factor is CPU power. Also keep in mind that SNMP v3, unlike SNMP v1 and v2c, does not scale with more CPU power. Because of this limitation, PRTG can only handle a limited number of requests per second so that you can use only a limited number of sensors using SNMP v3. If you see an increase in Interval Delay or Open Requests with the Probe Health sensor, distribute the load over multiple probes. SNMP v1 and SNMP v2c do not have this limitation.

Community String

This setting is only visible if you select SNMP v1 or SNMP v2c (recommended) above. Enter the community string of your device. This is like a clear-text password for simple authentication.

We recommend that you use the default value.

Authentication Method

This setting is only visible if you select SNMP v3 above. Select the authentication method:

• MD5: Use message-digest algorithm 5 (MD5) for authentication.
• SHA: Use Secure Hash Algorithm (SHA) for authentication.

If you do not want to use authentication but you need SNMP v3, for example, because your device requires context, you can leave the Password field empty. In this case, PRTG uses SNMP_SEC_LEVEL_NOAUTH and it entirely deactivates authentication.

The authentication method you select must match the authentication method of your device.

User Name

This setting is only visible if you select SNMP v3 above. Enter the user name for access to the target SNMP device.

The user name that you enter must match the user name of your device.

Password

This setting is only visible if you select SNMP v3 above. Enter the password for access to the target SNMP device.

The password that you enter must match the password of your device.

Encryption Type

This setting is only visible if you select SNMP v3 above. Select an encryption type:

• DES: Use Data Encryption Standard (DES) as the encryption algorithm.
• AES: Use Advanced Encryption Standard (AES) as the encryption algorithm.

Net-SNMP does not support AES-192 and AES-256. They do not have RFC specifications.

The encryption type that you select must match the encryption type of your device.

Encryption Key

This setting is only visible if you select SNMP v3 above. Enter an encryption key. If you provide a key, PRTG encrypts SNMP data packets with the encryption algorithm that you selected above. Enter a string or leave the field empty.

The encryption key that you enter must match the encryption key of your device. If the encryption keys do not match, you do not get an error message.

Context Name

This setting is only visible if you select SNMP v3 above. Enter a context name only if the configuration of the device requires it. Context is a collection of management information that is accessible by an SNMP device. Enter a string.

SNMP Port

Enter the port for the connection to the SNMP target device. Enter an integer. The default port is 161.

We recommend that you use the default value.

Timeout (Sec.)

Enter a timeout in seconds for the request. Enter an integer. The maximum timeout value is 300 seconds (5 minutes).

Port

Select the port that PRTG uses for connections to the monitored databases:

• Default (recommended): PRTG automatically determines the type of the database and uses the corresponding default port to connect. PRTG uses the following default ports:

• Microsoft SQL: 1433
• MySQL: 3306
• Oracle SQL: 1521
• PostgreSQL: 5432

• Custom port for all database sensors: Select this option if your database management systems do not use the default ports. Enter a custom port for database connections below.

PRTG uses this custom port for all database sensors and for connections to all your databases.

Custom Port

Enter a custom port for database connections. Enter an integer.

PRTG uses this custom port for all database sensors and for connections to all your databases.

Authentication Method

Select the authentication method for the connection to the Structured Query Language (SQL) database:

• Windows authentication with impersonation: PRTG uses the Windows credentials that you define in settings that are higher in the object hierarchy, for example, in the settings of the parent device; for the database connection.
  The user whose credentials PRTG uses needs to have permission to log in to the probe system with a database sensor. This is necessary for the impersonation.
• SQL server authentication: Use explicit credentials for database connections. Enter a user name and password below.

User Name

This setting is only visible if you select SQL server authentication above. Enter the user name for the database connection.

Password

This setting is only visible if you select SQL server authentication above. Enter the password for the database connection.

Timeout (Sec.)

Enter a timeout in seconds for the request. Enter an integer. The maximum timeout value is 300 seconds (5 minutes).

Access Key

Enter the Amazon Web Services (AWS) access key.

Secret Key

Enter the AWS secret key.

Tenant ID

Enter the Azure AD tenant ID.

A tenant ID must be a 32-digit sequence in hexadecimal notation.

Client ID

Enter the Azure AD client ID.

Client Secret

Enter the Azure AD client secret.

Placeholder 1 Description

Enter a description for Placeholder 1, for example information about the purpose or content of the placeholder.

Placeholder 1

Enter a value for the placeholder. PRTG inserts the value for the script execution if you add %scriptplaceholder1 in the argument list. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 2 Description

Enter a description for Placeholder 2, for example information about the purpose or content of the placeholder.

Placeholder 2

Enter a value for the placeholder. PRTG inserts the value for the script execution if you add %scriptplaceholder2 in the argument list. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 3 Description

Enter a description for Placeholder 3, for example information about the purpose or content of the placeholder.

Placeholder 3

Enter a value for the placeholder. PRTG inserts the value for the script execution if you add %scriptplaceholder3 in the argument list. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 4 Description

Enter a description for Placeholder 4, for example information about the purpose or content of the placeholder.

Placeholder 4

Enter a value for the placeholder. PRTG inserts the value for the script execution if you add %scriptplaceholder4 in the argument list. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 5 Description

Enter a description for Placeholder 5, for example information about the purpose or content of the placeholder.

Placeholder 5

Enter a value for the placeholder. PRTG inserts the value for the script execution if you add %scriptplaceholder5 in the argument list. PRTG does not display the value in the sensor log or the sensor's settings.

API Key

Enter an API key that the sensor uses for authentication against the Cisco Meraki Dashboard API.

User Name

Enter the user name for access to the Dell EMC system.

Password

Enter the password for access to the Dell EMC system.

Port

Enter the port for the connection to the Dell EMC system. The default port for secure connections is 443.

API Token

Enter the API token for access to the FortiGate system.

Port

Enter the port for the connection to the FortiGate system. The default port for secure connections is 443.

User Name

Enter the user name for access to the HPE 3PAR system.

Password

Enter the password for access to the HPE 3PAR system.

Protocol

Select the protocol that you want to use for the connection to the HPE 3PAR system:

• HTTPS (default): Use a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection.
• HTTP: Use an unsecure connection.

WSAPI Port

Enter the Web Services API (WSAPI) port for the connection to the HPE 3PAR system. The default port for secure connections is 8080 and the default port for unsecure connections is 8008.

For more information, see the Knowledge Base: Where can I find the Web Services API (WSAPI) port for the connection to the HPE 3PAR system?

SSH Port

Enter the SSH port for the connection to the HPE 3PAR system. The default port for secure connections is 22.

Tenant ID

Enter the Azure AD tenant ID.

A tenant ID must be a 32-digit sequence in hexadecimal notation.

Client ID

Enter the Azure AD client ID.

Client Secret

Enter the Azure AD client secret.

Subscription ID

Enter the Azure AD subscription ID.

Authentication Method

Select if you want to connect without credentials or define credentials for access to the MQTT broker.

• None (default): Connect without credentials.
• User name and password: Define credentials for the connection.

User Name

This setting is only visible if you select User name and password above. Enter the user name for access to the Message Queue Telemetry Transport (MQTT) broker.

Password

This setting is only visible if you select User name and password above. Enter the password for access to the MQTT broker.

Port

Enter the port for the connection to the MQTT broker. The default port for secure connections is 8883 and the default port for unsecure connections is 1883.

Transport-Level Security

Select if you want to use a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection:

• Do not use transport-level security: Establish the connection without connection security.
• Use transport-level security: Establish the connection with the strongest SSL/TLS method that the target device provides.

Server Authentication

This setting is only visible if you select Use transport-level security above. Select if you want to use a certificate for server authentication.

• Disable (default): Do not use a certificate for server authentication.
• Enable: Use a certificate for server authentication.

CA Certificate

This setting is only visible if you enable Server Authentication above. Paste the certificate authority (CA) certificate for the verification of the MQTT broker.

The certificate must be in Privacy-Enhanced Mail (PEM) format.

Client Authentication

This setting is only visible if you select Use transport-level security above. Select if you want to use a certificate for client authentication.

• Disable (default): Do not use a certificate for client authentication.
• Enable: Use a certificate for client authentication.

Client Certificate

This setting is only visible if you enable Client Authentication above. Paste the certificate that you created for authenticating the sensor against the MQTT broker.

The certificate must be in PEM format.

Client Key

This setting is only visible if you enable Client Authentication above. Enter the client key for access to the MQTT broker.

The client key must be in PEM format and it must be encrypted using the Client Key Password.

Client Key Password

This setting is only visible if you enable Client Authentication above. Enter the password for the client key.

User Name

Enter a user name for access to the ONTAP System Manager.

Password

Enter the password for access to the ONTAP System Manager.

Port

Enter the port for the connection to the ONTAP System Manager. The default port for secure connections is 443.

Protocol

Select the protocol that you want to use for the connection to the ONTAP System Manager. Choose between:

• HTTPS (default)
• HTTP

Port

Enter the port for the connection to the OPC Unified Architecture (OPC UA) server. The default port for secure connections is 4840.

Server Path

Enter the path of the OPC UA server endpoint if you run more than one server under the same IP address or DNS name.

Security Mode

Select if you want to use encryption:

• None (default): Do not use encryption.
• Sign: Sign messages between the sensor and the OPC UA server.
• Sign & Encrypt: Sign and encrypt messages between the sensor and the OPC UA server.

Security Policy

This setting is only visible if you select Sign or Sign & Encrypt above. Select if you want to use a security policy and define which policy you want to use:

• None (default): Do not use a security policy.
• Basic256Sha256: Use the Basic256Sha256 security policy.
• Basic256: Use the Basic256 security policy.

Client Certificate

Paste the certificate that you created for authenticating the sensor against the OPC UA server.

The certificate must meet the following requirements:

• The key size must be 2048-bit.
• The secure hash algorithm must be SHA256.
• DataEncipherment must be part of the KeyUsage certificate extension.
• A uniform resource indicator (URI) must be set in subjectAltName.
• The certificate must be in Privacy-Enhanced Mail (PEM) format.

Client Key

Enter the client key for access to the OPC UA server.

The client key must be in PEM format and it must be encrypted using the Client Key Password.

Client Key Password

Enter the password for the client key.

Authentication Method

Select if you want to connect without credentials or define credentials for access to the OPC UA server:

• Anonymous (default): Connect without credentials.
• User name and password: Define credentials for the connection.

Most OPC UA servers do not support User name and password authentication without a client certificate. To use User name and password authentication, select Sign or Sign & Encrypt under Security Mode and Basic256Sha256 or Basic256 under Security Policy and enter the Client Certificate, Client Key, and Client Key Password that you want to use.

User Name

This setting is only visible if you select User name and password above. Enter the user name for access to the OPC UA server.

Password

This setting is only visible if you select User name and password above. Enter the password for access to the OPC UA server.

Authentication Method

Select if you want to connect without credentials or define credentials for access to the Orchestra platform:

• None (default): Connect without credentials.
• User name and password: Define credentials for the connection.

User Name

This setting is only visible if you select User name and password above. Enter the user name for access to the Orchestra platform.

Password

This setting is only visible if you select User name and password above. Enter the password for access to the Orchestra platform.

Timeout (Sec.)

Enter a timeout in seconds for the request. Enter an integer. The maximum timeout value is 300 seconds (5 minutes).

Port

Enter the port for the connection to the Orchestra platform. The default port for secure connections is 8443 and the default port for unsecure connections is 8019.

Protocol

Select the protocol that you want to use for the connection to the Orchestra platform:

• HTTPS (default): Use a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection.
• HTTP: Use an unsecure connection.

User Name

Enter the user name for access to the Redfish system.

Password

Enter the password for access to the Redfish system.

Protocol

Select the protocol that you want to use for the connection to the Redfish system. Choose between:

• HTTPS (default): Use a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection.
• HTTP: Use an unsecure connection.

Port

Enter the port for the connection to the Redfish system. The default port for secure connections is 443.

Authentication Method

Select the authentication method for access to the Representational State Transfer (REST) application programming interface (API):

• None (default): Use no authentication.
• Basic authentication: Use basic authentication.
• Bearer authentication: Use an OAuth2 bearer token.

User Name

This setting is only visible if you select Basic authentication above. Enter the user name for access to the REST API.

Password

This setting is only visible if you select Basic authentication above. Enter the password for access to the REST API.

Bearer Token

This setting is only visible if you select Bearer authentication above. Enter a bearer token for access to the REST API.

Placeholder 1 Description

Enter a description for Placeholder 1, for example information about the purpose or content of the placeholder.

Placeholder 1

Enter a value for the placeholder. PRTG inserts the value for the REST API request if you add %restplaceholder1 in the Request URL, POST Body, and Custom Headers fields of the REST Custom v2 sensor. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 2 Description

Enter a description for Placeholder 2, for example information about the purpose or content of the placeholder.

Placeholder 2

Enter a value for the placeholder. PRTG inserts the value for the REST API request if you add %restplaceholder2 in the Request URL, POST Body, and Custom Headers fields of the REST Custom v2 sensor. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 3 Description

Enter a description for Placeholder 3, for example information about the purpose or content of the placeholder.

Placeholder 3

Enter a value for the placeholder. PRTG inserts the value for the REST API request if you add %restplaceholder3 in the Request URL, POST Body, and Custom Headers fields of the REST Custom v2 sensor. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 4 Description

Enter a description for Placeholder 4, for example information about the purpose or content of the placeholder.

Placeholder 4

Enter a value for the placeholder. PRTG inserts the value for the REST API request if you add %restplaceholder4 in the Request URL, POST Body, and Custom Headers fields of the REST Custom v2 sensor. PRTG does not display the value in the sensor log or the sensor's settings.

Placeholder 5 Description

Enter a description for Placeholder 5, for example information about the purpose or content of the placeholder.

Placeholder 5

Enter a value for the placeholder. PRTG inserts the value for the REST API request if you add %restplaceholder5 in the Request URL, POST Body, and Custom Headers fields of the REST Custom v2 sensor. PRTG does not display the value in the sensor log or the sensor's settings.

User Name

Enter the user name for access to the Veeam Backup Enterprise Manager.

Password

Enter the password for access to the Veeam Backup Enterprise Manager.

Port

Enter the port for the connection to the Veeam Backup Enterprise Manager. The default port for secure connections is 9398.

Preferred Data Source

This setting only applies to hybrid sensors that use both performance counters and Windows Management Instrumentation (WMI). The setting does not apply to other sensors.

Define the method that Windows sensors use to query data:

• Performance counters and WMI as fallback: Try to query data via performance counters. If this is not possible, establish a connection via WMI.

• Performance counters only: Query data via performance counters only. If this is not possible, the sensor returns no data.

• WMI only (recommended): Query data via WMI only. If this is not possible, the sensor returns no data. We recommend that you use this option.

Timeout Method

Select the time that the sensor waits for the return of the WMI query before the sensor cancels the query and shows an error message:

• Use 1.5× scanning interval (recommended): Multiply the scanning interval of the sensor by 1.5 and use the resulting value.
• Set manually: Manually enter a timeout value.

We recommend that you use the default value.

If you experience ongoing timeout errors, try increasing the timeout value.

Timeout (Sec.)

This setting is only visible if you select Set manually above. Enter the time the sensor waits for the return of its WMI query before it cancels it and shows an error message. Enter an integer. The maximum timeout value is 900 seconds (15 minutes).

SNMP Delay (ms)

Enter the time in milliseconds (ms) that PRTG waits between two SNMP requests. This can increase device compatibility. Enter an integer. You can define a delay between 0 and 100. PRTG does not support higher delays.

We recommend that you use the default value.

If you experience SNMP connection failures, try increasing the delay.

Failed Requests

Select if an SNMP sensor tries again after a request fails:

• Retry (recommended): Try again if an SNMP request fails. This can prevent false error messages because of temporary timeout failures.
• Do not retry: Do not retry if an SNMP request fails. If you select this option, an SNMP sensor shows a Down status earlier.

Overflow Values

Select how PRTG handles overflow values. Some devices do not correctly handle internal buffer overflows. This can cause false peaks.

• Ignore overflow values: Ignore overflow values and do not include them in the monitoring data. We recommend that you use this option.
• Handle overflow values as valid results: Regard all overflow values as regular data and include them in the monitoring data.

If you experience problems because of strange peaks in your data graphs, change this option. Peaks might indicate that the target device resets counters without an overflow. PRTG interprets such behavior as overflow that results in data peaks. Select the option Ignore overflow values in this case. For more details, see the Knowledge Base: What is the Overflow Values setting in the SNMP Compatibility Options?

Zero Values

Select how PRTG handles zero values. Some devices send incorrect zero values. This can cause false peaks.

• Ignore zero values for delta sensors (recommended): Ignore zero values and do not include them in the monitoring data. We recommend that you use this option.
  If you experience problems, try changing this option.
• Handle zero values as valid results for delta sensors: Regard all zero values as regular data and include them in the monitoring data.

32-bit/64-bit Counters

Select the type of traffic counters that PRTG searches for on a device:

• Use 64-bit counters if available (recommended): The interface scan uses 64-bit traffic counters, if available. This can avoid buffer overflows in the devices
   

We recommend that you use the default value.
If you experience problems, try changing this option.

• Use 32-bit counters only: The interface scan always uses 32-bit traffic counters, even if 64-bit counters are available. This can make monitoring more reliable for some devices.

Request Mode

Select the request method that PRTG uses for SNMP sensors:

• Use multi get (recommended): Bundle multiple SNMP requests into one request. We recommend that you use this option.
  If you experience problems, try changing this option.
• Use single get: Use one request for each SNMP value. This can increase compatibility with older devices.

PRTG uses paging for SNMP requests. This means that if a sensor has to query more than 20 object identifiers (OID), it automatically polls the OIDs in packages of 20 OIDs each.

Walk Mode

Select the kind of SNMP walk that PRTG uses for SNMP sensors:

• Use GETBULK requests (recommended): Request the next x OIDs in one SNMP request. The default value is 10. It is dynamic based on the response size.
  This option only works with devices that support SNMP as of version v2c. Make sure that you set the correct SNMP Version in the Credentials for SNMP Devices settings of the parent device or inherit it from objects that are higher in the object hierarchy.
• Use GETNEXT requests: Request one OID at a time. This can increase compatibility with older devices or with devices that have insufficient SNMP BULKWALK support.

Port Name Template

Select how PRTG displays the name of SNMP sensors. Enter a template that uses several variables. When you add new sensors, PRTG scans the interface for available counters at certain OIDs. At each OID, several fields with interface descriptions are usually available. They are different for every device and OID. PRTG uses the information in these fields to name the sensors. If a field is empty or if it is not available, PRTG adds an empty string to the name. By default, the port name template is ([port]) [ifalias] [ifsensor], which creates a name like (001) Ethernet1 Traffic. You can use and combine any field names that are available at an OID of your device, for example:

• [port]: The port number of the monitored interface.
• [ifalias]: The 'alias' name for the monitored interface as specified by a network manager, providing a non-volatile handling.
• [ifname]: The textual name of the monitored interface as assigned by the local device.
• [ifdescr]: A textual string containing information about the target device or interface, for example, manufacturer, product name, or version.
• [ifspeed]: An estimate of the monitored interface's current bandwidth (Kbit/s).
• [ifsensor]: The type of the sensor, this is Traffic or RMON. This helps to differentiate between SNMP Traffic and SNMP RMON sensors.

For more information about SNMP sensor names, see the Knowledge Base: How can I change the defaults for names automatically generated for new SNMP sensors?

Port Name Update

Select how PRTG reacts if you change the names of ports in your physical device (for example, a switch or router):

• Keep port names (use this if you edit the names in PRTG): Do not automatically adjust sensor names. This is the best option if you want to manually change names in PRTG.

• Automatically update sensor names if port names change in the device: If PRTG detects port name changes in your physical device, it tries to automatically adjust the sensor names accordingly.

For more information about automatic name updates, see the Knowledge Base: SNMP Traffic sensors when the device changes them.

Port Identification

Select the field that PRTG uses for SNMP interface identification:

• Automatic identification (recommended): Try the ifAlias field first to identify an SNMP interface and then try ifDescr.
  PRTG does not automatically try ifName.
• Use ifAlias: For most devices, ifAlias is the best field to use for unique interface names.
• Use ifDescr: Use this option if the port order of your device changes after a restart, and if no ifAlias field is available. For example, this is the best option for Cisco ASA devices.
  If you use this option, it is important that your device returns unique interface names in the ifDescr field.
• Use ifName: You can also use this option if no unique ifAlias is available.
  If you use this option, it is important that your device returns unique interface names in the ifName field.
• Do not update ports: Use this option to disable the automatic port identification.

Start Interface Index

This setting only applies to SNMP Traffic sensors and to Cisco IP SLA sensors.

Enter the index at which PRTG starts to query the interface range during sensor creation. Enter 0 for the automatic mode.

We recommend that you use the default value.

End Interface Index

This setting only applies to SNMP Traffic sensors and to Cisco IP SLA sensors.

Enter the index at which PRTG stops querying the interface range during sensor creation. Enter 0 for the automatic mode.

We recommend that you use the default value.

IP Address/DNS 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 port is 8080. Enter an integer.

User Name

If the proxy requires authentication, enter the user name for the proxy login.

Only basic authentication is available. Enter a string or leave the field empty.

Password

If the proxy requires authentication, enter the password for the proxy login.

Only basic authentication is available. Enter a string or leave the field empty.

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:

• 30 seconds
• 60 seconds
• 5 minutes
• 10 minutes
• 15 minutes
• 30 minutes
• 1 hour
• 4 hours
• 6 hours
• 12 hours
• 24 hours

You can change the available intervals in the system administration of PRTG Network Monitor.

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 target device only has temporary issues. For previous scanning intervals with failed requests, the sensor shows the Warning status. Choose from:

• Set sensor to down status immediately: Set the sensor to the Down status immediately after the first request fails.
• Set sensor to warning status for 1 interval, then set to down status (recommended): Set the sensor to the Warning status after the first request fails. If the second request also fails, the sensor shows the Down status.
• Set sensor to warning status for 2 intervals, then set to down status: Set the sensor to the Down status only after the third request fails.
• Set sensor to warning status for 3 intervals, then set to down status: Set the sensor to the Down status only after the fourth request fails.
• Set sensor to warning status for 4 intervals, then set to down status: Set the sensor to the Down status only after the fifth request fails.
• Set sensor to warning status for 5 intervals, then set to down status: Set the sensor to the Down status only after the sixth request fails.

Sensors that monitor via Windows Management Instrumentation (WMI) always wait at least one scanning interval before they show the Down status. It is not possible to immediately set a WMI sensor to the Down status, so the first option does not apply to these sensors. All other options can apply.

If you define error limits for a sensor's channels, the sensor immediately shows the Down status. None of the interval options apply.

If a channel uses lookup values, the sensor immediately shows the Down status. None of the interval options apply.

Exclude Cluster Nodes

This setting is only visible if you have a failover cluster.

Sometimes you want to keep a cluster node from monitoring the sensors that run on this probe, group, or device, for example, if a device is not reachable from every cluster node. Select the cluster nodes that you do not want to include in sensor scans. By default, all objects underneath the probe inherit this setting.

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:

• None
• Saturdays
• Sundays
• Weekdays
• Weekdays Eight-To-Eight (08:00 - 20:00)
• Weekdays Nights (17:00 - 09:00)
• Weekdays Nights (20:00 - 08:00)
• Weekdays Nine-To-Five (09:00 - 17:00)
• Weekends

You can create schedules, edit schedules, or pause monitoring for a specific time span. For more information, see section Schedules.

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:

• Do not set up a one-time maintenance window: Do not set up a one-time maintenance window. Monitoring is always active.
• Set up a one-time maintenance window: Set up a one-time maintenance window and pause monitoring. You can define a time span for the pause below.

To close an active one-time maintenance window before the defined end date, change the time entry in Maintenance Ends to a date in the past.

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:

• Use parent: Use the dependency type of the parent object.
• Select a sensor: Use the dependency type of the parent object. Additionally, pause the current object if a specific sensor is in the Down status or in the Paused status because of another dependency.

You do not trigger a status change by dependency if you manually pause a master sensor or if you pause it by schedule.

To test your dependencies, select Simulate Error Status from the context menu of an object that other objects depend on. A few seconds later, all dependent objects are paused. You can check all dependencies under Devices | Dependencies in the main menu bar.

Dependency

This setting is only visible if you enable Select a sensor above. Click and use the object selector to select a sensor on which the current object will depend.

Dependency Delay (Sec.)

This setting is only visible if you select 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.

User Group Access

Select the user groups that have access to the object. 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:

• Inherited: Inherit the access rights settings of the parent object.
• No access: Users in this user group cannot see or edit the object. The object neither shows up in lists nor in the device tree.
  There is one exception: If a user in this user group has access to a child object, the parent object is visible in the device tree but users in this user group cannot access it.
• Read access: Users in this group can see the object and view its monitoring results. They cannot edit any settings.
• Write access: Users in this group can see the object, view its monitoring results, and edit its settings. They cannot edit its access rights settings.
• Full access: Users in this group can see the object, view its monitoring results, edit its settings, and edit its access rights settings.

To automatically set all child objects to inherit this object's access rights, enable the Revert access rights of child objects to "inherited" option.

For more details on access rights, see section Access Rights Management.

Channel Unit Types

For each type of channel, select the unit in which PRTG displays the data. If you define this setting on probe, group, or device level, you can inherit these settings to all sensors underneath. You can set units for the following channel types (if available):

• Bandwidth
• Memory
• Disk
• File
• Custom

Custom channel types are only available on sensor level.

Unusual Detection

Select if you want to use the unusual detection for sensors:

• Enabled: Activates the unusual detection for this object and, by default, for all objects underneath in the object hierarchy. Sensors that are affected by this setting show the Unusual status if PRTG detects unusual activity.
• Disabled: Does not activate the unusual detection. PRTG ignores unusual values for sensors that are affected by this setting. These sensors do not show the Unusual status.

You can configure the behavior of the unusual detection or completely disable it in the system settings.

Similar Sensors Detection

Select if you want to activate the similar sensors analysis:

• Enabled: Activates the similar sensors detection for this object and, by default, for all objects underneath in the object hierarchy. PRTG considers all sensors that are affected by this setting during the similarity analysis.
• Disabled: Does not activate the similar sensors detection. PRTG does not consider sensors that are affected by this setting during the similarity analysis.

You can configure the depth of the analysis of the similar sensors detection or completely disable it in the system settings.

System Information

Select if you want to retrieve and show system information for your devices:

• Enabled: Activates the system information feature for this object and, by default, for all objects underneath in the hierarchy.
• Disabled: Does not activate the system information feature.

The System Information feature is enabled by default. To retrieve the data, PRTG automatically uses the credentials for Windows systems and the credentials for SNMP devices that you entered in the device settings or that the device inherits from a parent object like the root group. Consider this when you monitor devices that are outside of your local network, especially when you use SNMP v1 or SNMP v2c, which do not provide encryption.

This setting is not available on the hosted probe of a PRTG Hosted Monitor instance.

Outgoing IPv4

Define the IP address for outgoing requests that use the IPv4 protocol. The list shows all available IP addresses on the system. Choose a specific IP address or select auto.

Outgoing IPv6

Define the IP address for outgoing requests that use the IPv6 protocol. The list shows all available IP addresses on the system. Choose a specific IP address or select auto.

For more information, see section IPv6 Support.

Cluster Connectivity

This setting is only visible if you have a failover cluster.

Define if the remote probe connects to all cluster nodes or only to the primary master node:

• Remote probe sends data only to primary master node: The remote probe only connects to the primary master node. You are not able to review monitoring data on failover nodes. Consider this option if you have bandwidth limitations in your network or if the remote probe cannot access your failover nodes.
• Remote probe sends data to all cluster nodes: The remote probe connects to all cluster nodes and sends monitoring data to the failover nodes in addition to the primary master node. The remote probe is visible on all of your cluster nodes as soon as it automatically connects to the correct IP addresses and ports of the failover nodes. If the primary master node fails, you can still see monitoring data of the remote probe.

PRTG does not notify you if a remote probe is disconnected from a cluster node. Therefore, explicitly check on a cluster node if remote probes are connected (for example, via the device tree in the PRTG web interface on a cluster node).

Restart Options

Define if you want to schedule an automatic restart:

• No scheduled system or service restart: Do not automatically perform a scheduled restart of services. We recommend that you manually restart the PRTG core server system every few weeks. You can initiate a restart of the PRTG probe service in the Administrative Tools in the PRTG web interface.
• Scheduled restart of PRTG services: Restart the PRTG probe service on the probe system. If you select this option on the local probe, the PRTG core server service restarts as well. Define a schedule under Restart Schedule.
• Scheduled system restart (recommended): Define a schedule under Restart Schedule. We recommend that you restart probe systems once a month for best performance.

Restart Schedule

This setting is only visible if you select a schedule option above. Choose how often you want to restart the PRTG probe service or the probe system:

• Once per week: Select a day and a time below.
• Once per month (recommended): Select a day of the month and a time below.

Day

This setting is only visible if you select a schedule option above. Select a day of the week (Monday to Sunday) or month (1st to 30th or Last). If you select Last, PRTG restarts the PRTG core server system on the last day of the month, regardless of how many days the month has.

Time

This setting is only visible if you select a schedule option above. Select a time for the planned restart.

You get a Windows warning message 10 minutes before the restart to inform you about the restart if you are logged in to PRTG. The actual restart time can differ by up to 30 minutes from the time you enter here.