User Experience Insight sensors continuously test and provide information about the uptime and reachability of important services for end-users.

The customizable Generic Test template is typically used to analyze basic connectivity to a user-defined target host. The target host can be configured as an IP address or a fully-qualified domain name. UXI sensors test connectivity to the host using up to four selected TCP ports and ICMP Ping.

For applications such as SSH, you might be interested in knowing the SSH version used on the remote host or (if available) the remote hostname. For this information, you can use the Telnet test template.

The Telnet test template verifies connectivity every test cycle to a TCP port, similar to the generic test. Additionally, the Telnet test will periodically telnet to the remote device at a specified port and verify if a matching string is present in the output.

For example, when you Telnet to a device on an SSH port, you might typically see output such as:

You can use this information to verify the sensor is able to connect and the correct SSH version is present in the output. In this example the test template would look like this.

When the test is successful, you will see the latency, jitter, packet loss, and the elapsed time it took to establish the connection and verify the output, as shown below.

Because the test directly checks for the presence of an output string in its established tunnel, if the output is not present or the sensor is unable to connect to the SSH port, you will see an error in the status section on the left.

Here is an example where the searched string was not present:

The string field is a mandatory configuration to include for the test itself, if the string is not present then the test simply represents a TCP ping to an open port.