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 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 to know 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 will verify connectivity every test cycle to a TCP port similar to the generic test. In addition, 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, typically you will see output such as
$ telnet 192.168.1.7 22
Connected to 192.168.1.7.
Escape character is '^]'.
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 elapsed time it took to establish the connection and verify the output as shown below.
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.