References > Component Monitor Types > HTTP Monitors > HTTP Monitor

HTTP monitor

This component monitor tests a web server's ability to accept incoming sessions and transmit the requested page. The component monitor can optionally search the delivered page for specific text strings and pass or fail the test based on that search.

The HTTP Monitor measures the time it takes the HTTP “get” for the page referenced in the component monitor to load. This response time is measured in milliseconds.

If a web page redirects to another page, the response time measures the entire time from the original request until the last redirected page is loaded.

This monitor supports the following additional macros:

  • ${Node.SysName}
  • ${Node.Caption}
  • ${Node.DNS}
  • ${Node.ID}

Statistic

This component monitor does not compute a statistic.

Polling using Orion agent for Linux

This component monitor has the following limitations for Orion agent for Linux polling methods.

Does not support Kerberos authentication. Only basic and digest authentication types are supported when this probe runs using Orion agent for Linux. For Kerebos authentication on a Linux-based computer, select Agentless for the Preferred Polling Method on the monitor.

Field Descriptions

Description

This field provides a default description of the monitor. You have the ability to override the default description by adding to or replacing the text, which is automatically saved. The variable to access this field is ${UserDescription}.

Enable Component

Determines whether the component is enabled. Disabling the component leaves it in the application in a deactivated state not influencing either SolarWinds SAM application availability or status.

Credential for Monitoring

If the web site is password-protected, select a credential that can access the web site. If the credential you need is not already present in the credentials list, use the Quick Credentials section to add a new credential.

If the web site is not password protected, do not specify a credential.

Port Number

The port used for the web site. The default value is 80.

Url

This field allows you to specify the URL you want to monitor. The SolarWinds SAM variables contained in the default value for this field attempt to monitor a web site at the IP address of the assigned node ${IP} and on the port specified in the Port Number field ${PORT}.

Proxy Servers: To prevent proxy servers from caching the monitored URL, you can append a unique query string to the URL with the ${TimeStamp} variable.

Example "cache buster" for simple URL: http://${IP}:${Port}/?_cb=${TimeStamp}

Example "cache buster" for URL with existing query string:
http://${IP}:${Port}/?page.aspx?var=value&_cb=${TimeStamp}

Host Header

Enter the address of the host header. For example, www.solarwinds.com.

Host Request

Enter the type of content. For example, POST.

Follow Redirect

This allows you to specify the component monitor to automatically follow server-side redirects.

Use Proxy

This check box allows you to use a web proxy to access the web site.

Proxy Address

This field allows you to specify the address of a web proxy to access the web site.

User Agent

This field allows you to emulate a specific user agent or browser type when contacting the web site. For example, to emulate Internet Explorer version 7, type Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 6.0). For more information about user agent strings, see http://www.useragentstring.com

Search String

This field contains the text string indicating successful page retrieval. If the specified string is found in the web page content, the monitor is considered up.

The search string is not case-sensitive.

Fail if Found

This check box allows you to reverse the default behavior of the search string. If the search string is found in the web page content, the monitor is considered down instead of up.

Head Request

This field allows you to ensure the web site responds to the HTTP protocol, but without checking the validity of the web page content. Search strings are ignored if you select this option.

Accept Compression

If checked, indicates that compression is supported.

Response Time Threshold

This field allows you to set the warning or critical threshold conditions based on the response time. The response time is the time in milliseconds it takes SolarWinds SAM to determine that a component is not Down and to retrieve any statistical data. See setting Application Monitor Thresholds for more information.

User Notes

This field allows you to add notes for easy reference. You can access this field by using the variable, ${UserNotes}.