> Services > HTTP Service

HTTP Service

The Hyper Text Transfer Protocol (HTTP) service monitors a Web server to ensure it is running and publishing Web pages without reporting any errors. You must add the HTTP service on the Web server, which you must add as a device in MSP N-central

The HTTP service also includes Web Transaction Service (WTS) functionality that monitors the specific content on a Web site 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.

During the monitoring process, the HTTP service first attempts to resolve the domain name system (DNS) entry for the Web server. If the DNS test is successful, the service then checks the availability and response time of the Web server using a specified URL. If the DNS test is not successful, the service changes to the Misconfigured state. A code in the response header from the Web server determines whether the server is in a Normal, Warning, or Failed state. The Normal or Warning response codes are tracked as parameters on the status dashboard. The Failed response codes are automatically change the service to the Failed state.

To avoid potential security risks, we recommend that you configure this service to use an account that has limited privileges. A potential security risk exists when generating a Configuration Summary Report for this service. This report will display all of the service's parameters including the passwords for the accounts that are used by the HTTP service to monitor Web servers.

Service Type

TCP

Instances on a Device

20

Device Class

Server - Generic, Other, Printer, Scanner/Camera, Switch/Router, Workstation - Windows, Workstation - Generic, and Server - Windows

Monitored By

Windows probe, Central Server

Scan Interval

5 minutes

Timeout Value

The time (in seconds) that the MSP N-central server waits before considering the test a failure. The default is 30 seconds.

Port Number

80

Validation String

HTTP. This field displays a predefined set of characters that the system compares to the response to determine whether the response is valid.

HTTP 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, or
  • http://www.xyz.com/

A partial URL of the network address of the Web server can also be used.

Login Username

The username that is used to sign in to the designated URL. The Login Username can be used for latency testing but does not need to be configured if the designated web page does not require credentials.

Login Password

The security password used to sign in to the designated URL. You can use the Login Password for latency testing, however you do not need to configure it if the designated web page does not require credentials.

Authentication Scheme

The security authentication scheme used by the designated URL for determining whether requests for access are valid or not. This property should be configured as one of:

  • Basic,
  • Digest,
  • NTLM,
  • Kerberos, or
  • Negotiate.

Normal Response Code

The 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.

Status Detail

Description

HTTP Service Availability

The availability of a Web server based on the response code returned by the HTTP response header.

Average Round Trip Time (ms)

The average time for a request to be sent and received.

DNS Resolution

The FQDN or 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.

Content Verification Regular Expression

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

HTTP Status Code Definitions to HTTP or HTTPS Service Availability

The three possible values for HTTP Service Availability or 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, MSP N-central evaluates the following 'HTTP or HTTPS Status Code Definitions' as Normal (HTTP or HTTPS Service Availability 1):

Status Code Definition RFC Description HTTP or HTTPS Service Availability
100 Continue RFC 2616 Section 10.1.1 Normal (1)
101 Switching Protocols RFC 2616 Section 10.1.2 Normal (1)
200 OK RFC 2616 Section 10.2.1 Normal (1)
201 Created RFC 2616 Section 10.2.2 Normal (1)
202 Accepted RFC 2616 Section 10.2.3 Normal (1)
203 Non-Authoritative Information RFC 2616 Section 10.2.4 Normal (1)
204 No Content RFC 2616 Section 10.2.5 Normal (1)
205 Reset Content RFC 2616 Section 10.2.6 Normal (1)
206 Partial Content RFC 2616 Section 10.2.7 Normal (1)

Warning

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

Status Code Definition RFC Description HTTP or HTTPS Service Availability
300 Multiple Choices RFC 2616 Section 10.3.1 Warning (2)
301 Moved Permanently RFC 2616 Section 10.3.2 Warning (2)
302 Found RFC 2616 Section 10.3.3 Warning (2)
303 See Other RFC 2616 Section 10.3.4 Warning (2)
304 Not Modified RFC 2616 Section 10.3.5 Warning (2)
305 Use Proxy RFC 2616 Section 10.3.6 Warning (2)
306 (Unused) RFC 2616 Section 10.3.7 Warning (2)
307 Temporary Redirect RFC 2616 Section 10.3.8 Warning (2)

Failed

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

Status Code Definition RFC Description HTTP or HTTPS Service Availability
<Unspecified> <Unspecified> Any value not previously specifed as 'Normal (1)' or 'Warning (2)' Failed: 0 Failed (0)
400 Bad Request RFC 2616 Section 10.4.1 Failed (0)
401 Unauthorized RFC 2616 Section 10.4.2 Failed (0)
402 Payment Required RFC 2616 Section 10.4.3 Failed (0)
403 Forbidden RFC 2616 Section 10.4.4 Failed (0)
404 Not Found RFC 2616 Section 10.4.5 Failed (0)
405 Method Not Allowed RFC 2616 Section 10.4.6 Failed (0)
406 Not Acceptable RFC 2616 Section 10.4.7 Failed (0)
407 Proxy Authentication Required RFC 2616 Section 10.4.8 Failed (0)
408 Request Timeout RFC 2616 Section 10.4.9 Failed (0)
409 Conflict RFC 2616 Section 10.4.10 Failed (0)
410 Gone RFC 2616 Section 10.4.11 Failed (0)
411 Length Required RFC 2616 Section 10.4.12 Failed (0)
412 Precondition Failed RFC 2616 Section 10.4.13 Failed (0)
413 Request Entity Too Large RFC 2616 Section 10.4.14 Failed (0)
414 Request-URI Too Long RFC 2616 Section 10.4.15 Failed (0)
415 Unsupported Media Type RFC 2616 Section 10.4.16 Failed (0)
416 Requested Range Not Satisfiable RFC 2616 Section 10.4.17 Failed (0)
417 Expectation Failed RFC 2616 Section 10.4.18 Failed (0)
500 Internal Server Error RFC 2616 Section 10.5.1 Failed (0)
501 Not Implemented RFC 2616 Section 10.5.2 Failed (0)
502 Bad Gateway RFC 2616 Section 10.5.3 Failed (0)
503 Service Unavailable RFC 2616 Section 10.5.4 Failed (0)
504 Gateway Timeout RFC 2616 Section 10.5.5 Failed (0)
505 HTTP Version Not Supported RFC 2616 Section 10.5.6 Failed (0)