HTTPS service

When this service has a scan interval of less than 5 minutes, the agent may take longer than the scan interval to gather the metrics. As a result, you may notice some scan intervals are not populated.

The HTTPS service monitors all of the scan details of the HTTP service and the validity and expiry date of an SSL certificate on a device.

You can monitor the scan details for the SSL certificates only if the certificates have been signed by a CA that has been uploaded in N-able N-central or is listed in the default CA certificate file provided by N-able N-central.  For more information on uploading a certificate, see Uploading a certificate.

The HTTPS service does not currently provide the ability to interact with web sites that use self-signed certificates.

When performing Regex matching, the service looks at the whole web response, including the HTTP/HTTPS header and the page content, not only the page content.

The HTTPS service also includes WTSS functionality that monitors the specific content on a web site over a secure web connection by searching for a matching regular expression. For example, you can monitor the availability of specific content on an e-commerce site that uses a database driven architecture. The results from monitoring are displayed on the status dashboard under the HTTP service. If specified, the results can also be provided in any notifications triggered by the service.

Content Validation Failure!

If an HTTP URL redirects to HTTPS, then the content verification of compressed connections will fail.

The N-able N-central HTTPS service does not support forms-based authentication.

Service TypeTCP
Instances on a Device20
Device ClassServer - Generic, Other, Printer, Scanner/Camera, Switch/Router, Workstation - Windows, Workstation - Generic, and Server - Windows
Monitored ByWindows probe, N-able N-central server
Scan Interval5 minutes
Minimum Scan Interval1 minute
Timeout ValueThe time that the N-able N-central server waits before considering the test a failure. The default is 30 seconds.
Port Number443
HTTPS URL

The URL used to test the availability of the web server.

For example:

  • www.xyz.com, index.html
  • http://www.xyz.com/index.html
  • http://www.xyz.com/

A partial URL is accessed using the network address of the web server.

When setting up the URL, an issue occurs if the first portion of the relative URL can be resolved by the monitoring device as a domain name.

For example, if you were monitoring https://192.168.1.1/example.com/index.html, and only provided the relative URL /example.com/index.html, the monitoring device will determine that the first portion is a domain name and assume an absolute URL was provided. As a workaround, you can configure the HTTPS service with the absolute URL manually.

Login UsernameThe username used to sign in to the designated URL. You can use the Login Username for latency testing, but you do not need to configure it if the web page does not require credentials.
Login PasswordThe security password used to sign in to the designated URL. You can use the Login Password for latency testing, but you do not need to configure it if the web page does not require credentials.
Authentication Scheme

The security authentication scheme used by the designated URL for determining if requests are valid or not. Configure this property using one of:

  • Basic
  • Digest
  • NTLM
  • Kerberos
  • Negotiate
Normal Response CodeThe codes in the response header that indicate a Normal state.
Warning Response Code

The codes in the response header that indicate a Warning state.

Any codes in the response header that are not configured as either a Normal Response Code or a Warning Response Code will result in the service being transitioned into a Failed state.

Content Verification Regular Expression

The regular expression used to find a specific match in the content on the web page. For example: The page cannot be displayed.

Content Validation Failure!

If an HTTP URL redirects to HTTPS, then the content verification of compressed connections will fail.

 

Status DetailDescription
HTTPS Service Availability

The availability of a web server based on the response code returned by the HTTPS response header.

This will appear as Failed if the a CA certificate of the Web server has not been uploaded or if it is not in the default a CA certificate file.

Round Trip Time (ms)The time for a request to be sent and received.
DNS Resolution

The FQDN and IP address that determines whether the device name can be resolved.

If an FQDN has been specified, the service searches for its IP address. If the IP address is found, the state will be Normal. Otherwise, it will be Failed, based on the default settings.

If an IP address has been specified, the service checks only the IP address' format. If the format is correct, the state will be Normal. Otherwise, it will be Failed, based on the default settings.

Server Certificate SignatureThe validity of the SSL certificate, indicated as either valid or invalid.
Server Certificate Expiration (days)The number of days remaining before the expiration of the SSL certificate.
Content Verification Regular Expression

The regular expression that triggers the status for the matched contents on the Web page.

Content Validation Failure!

If an HTTP URL redirects to HTTPS, then the content verification of compressed connections will fail.

HTTP Status code definitions to HTTPS service availability

The three possible values for HTTPS Service Availability (Normal: 1, Warning: 2, and, Failed: 0) are based on HTTP Status Code Definitions. RFC 2616 'Hypertext Transfer Protocol -- HTTP/1.1' defines the protocol referred to as "HTTP/1.1". This protocol includes more stringent requirements than HTTP/1.0 in order to ensure reliable implementation of its features.

Normal

By default, N-able N-central evaluates the following "HTTP or HTTPS Status Code Definitions" as
Normal (HTTP or HTTPS Service Availability 1):

Status CodeDefinitionRFC DescriptionHTTP or HTTPS Service Availability
100ContinueRFC 2616 Section 10.1.1Normal (1)
101Switching ProtocolsRFC 2616 Section 10.1.2Normal (1)
200OKRFC 2616 Section 10.2.1Normal (1)
201CreatedRFC 2616 Section 10.2.2Normal (1)
202AcceptedRFC 2616 Section 10.2.3Normal (1)
203Non-Authoritative InformationRFC 2616 Section 10.2.4Normal (1)
204No ContentRFC 2616 Section 10.2.5Normal (1)
205Reset ContentRFC 2616 Section 10.2.6Normal (1)
206Partial ContentRFC 2616 Section 10.2.7Normal (1)

Warning

By default, N-able N-central evaluates the following 'HTTP Status Code Definitions' as Warning (HTTP or HTTPS Service Availability 2):

Status CodeDefinitionRFC DescriptionHTTP or HTTPS Service Availability
300Multiple ChoicesRFC 2616 Section 10.3.1Warning (2)
301Moved PermanentlyRFC 2616 Section 10.3.2Warning (2)
302FoundRFC 2616 Section 10.3.3Warning (2)
303See OtherRFC 2616 Section 10.3.4Warning (2)
304Not ModifiedRFC 2616 Section 10.3.5Warning (2)
305Use ProxyRFC 2616 Section 10.3.6Warning (2)
306(Unused)RFC 2616 Section 10.3.7Warning (2)
307Temporary RedirectRFC 2616 Section 10.3.8Warning (2)

Failed

By default, N-able N-central evaluates the following 'HTTP Status Code Definitions' as Failed (HTTP or HTTPS Service Availability 0):

Status CodeDefinitionRFC DescriptionHTTP or HTTPS Service Availability
<Unspecified><Unspecified>Any value not previously specifed as 'Normal (1)' or 'Warning (2)' Failed: 0Failed (0)
400Bad RequestRFC 2616 Section 10.4.1Failed (0)
401UnauthorizedRFC 2616 Section 10.4.2Failed (0)
402Payment RequiredRFC 2616 Section 10.4.3Failed (0)
403ForbiddenRFC 2616 Section 10.4.4Failed (0)
404Not FoundRFC 2616 Section 10.4.5Failed (0)
405Method Not AllowedRFC 2616 Section 10.4.6Failed (0)
406Not AcceptableRFC 2616 Section 10.4.7Failed (0)
407Proxy Authentication RequiredRFC 2616 Section 10.4.8Failed (0)
408Request TimeoutRFC 2616 Section 10.4.9Failed (0)
409ConflictRFC 2616 Section 10.4.10Failed (0)
410GoneRFC 2616 Section 10.4.11Failed (0)
411Length RequiredRFC 2616 Section 10.4.12Failed (0)
412Precondition FailedRFC 2616 Section 10.4.13Failed (0)
413Request Entity Too LargeRFC 2616 Section 10.4.14Failed (0)
414Request-URI Too LongRFC 2616 Section 10.4.15Failed (0)
415Unsupported Media TypeRFC 2616 Section 10.4.16Failed (0)
416Requested Range Not SatisfiableRFC 2616 Section 10.4.17Failed (0)
417Expectation FailedRFC 2616 Section 10.4.18Failed (0)
500Internal Server ErrorRFC 2616 Section 10.5.1Failed (0)
501Not ImplementedRFC 2616 Section 10.5.2Failed (0)
502Bad GatewayRFC 2616 Section 10.5.3Failed (0)
503Service UnavailableRFC 2616 Section 10.5.4Failed (0)
504Gateway TimeoutRFC 2616 Section 10.5.5Failed (0)
505HTTP Version Not SupportedRFC 2616 Section 10.5.6Failed (0)

Status Code 401: before the release of 2023.4, Status Code 401 was categorized as "Normal". From 2023.4 onwards Status Code 401 is categorized as "Failed".