Probe Reference Overview

Use the Probe Picker window to choose the probe you want to use to query the device.


Set Probe Window

Using the Probe Selection Window

About the Probes

InterMapper comes with a large number of built-in probes. For a full index and detailed descriptions of built-in probes, see the Probe Index.

Packet-based probes

Probes such as "Ping/Echo", "SNMP MIB-II", "NNTP" and "RADIUS" send UDP packets to the device being tested and await a correctly formatted response.

Probe timeout period

The timeout period for waiting is configured by choosing Set Timeout from the Set Probe Info submenu. If no response is received within the timeout period, InterMapper tries again by sending another request packet. This process is repeated until either a response is received, or the number of requests sent exceeds the "Number of Lost Packets" threshold set for the map (a default of 3).

Response packet integrity

All packet-based probes check the integrity of the response they receive, and some can set the status of the device (Alarm, Warning, or OK) based on the severity of a problem.

TCP-based probes

Probes like "HTTP", "SMTP", and "LDAP" and others test the ability of a server to accept a TCP connection on a specific listening port, and to respond to a scripted interchange.

What happens in a TCP-based interchange

  1. InterMapper first attempts to connect to the specified port at the device's address.
  2. If this connection attempt fails, InterMapper shows the device in the DOWN state.

    If InterMapper successfully connects to the listening port, InterMapper sends protocol-specific commands through the TCP connection to test the server's responses and compare them to expected values.
  3. InterMapper changes the status of the device (e.g. ALARM, WARNING, OKAY, DOWN) if an error condition is detected, or if the execution of InterMapper's probe is interrupted for any reason.
  4. If InterMapper doesn't receive a proper response for 60 seconds, or if the TCP connection is lost while waiting for a response, the InterMapper probe will set status of the device to the proper condition.

Miscellaneous Probes

InterMapper has several "miscellaneous probes", described briefly below. They are described in detail in Miscellaneous Probes.