nt (Net Test) - A versatile network testing tool that supports ICMP, HTTP(s), DNS, TCP, and MTU testing

nt is a versatile tool for network troubleshooting and testing written in Go. It provides continuous testing of network connectivity using various protocols using subcommands, including icmp, tcp, http, and dns. Monitor round-trip times (RTT), track packet loss rates, and log high latency events with timestamps to ensure your network's reliability.

Table of Contents

• Features
• Installation
  • Option 1 - go install
  • Option 2 - build from source
  • Option 3 - Makefile
  • Option 4 - Download from Release
• Usage
  • Main Command
  • ICMP Ping Sub-Command
  • TCP Ping Sub-Command
  • HTTP Ping Sub-Command
  • DNS Ping Sub-Command
  • MTU Discovery Sub-Command
  • TCP Scan Sub-Command
• Logging and Recording
• License
• Contact

Features

• Subcommands for Protocols: Use specific subcommands (icmp, tcp, http, dns) to perform tests.
• Continuous ICMP Ping: Monitor network latency and packet loss using ICMP echo requests.
• TCP Connectivity Testing: Check the availability and response times of TCP ports.
• HTTP/HTTPS Testing: Test web server availability and measure HTTP/HTTPS response times.
• DNS Ping: Verify DNS server responsiveness and resolve lookup times.
• MTU Testing: Determine the Maximum Transmission Unit (MTU) size to a given destination host/IP.
• TCP Port Testing: Test if the remote server is listening on one or multiple given TCP ports.
• Recording and Logging: Save test results to a CSV file for later analysis.
• Customizable Output: Adjust the number of rows displayed in the terminal during live tests.
• Cross-Platform: Compatible with Windows and Linux.

Installation

Prerequisites

• For Option 1 & 2, Go 1.18 or higher is required on your system.

Option 1: Install via go install

The compiled executable will be placed in $GOPATH/bin

go install github.com/djian01/nt@latest

Option 2: Build from Source

git clone https://github.com/djian01/nt.git
cd nt
go build .

Option 3: Makefile (Docker & Make are required on your system)

The compiled executable will be placed in \executable\ inside the code folder

git clone https://github.com/djian01/nt.git
cd nt
make build-linux

or

git clone https://github.com/djian01/nt.git
cd nt
make build-windows

Option 4: Download Executable from GitHub Releases

1. Visit the Releases page of the repository.
2. Download the nt_linux_amd64_x.x.x.tar.gz file for Linux or the nt_windows_amd64_x.x.x.zip file for Windows

Usage

Main Command

nt [flags] <sub-command: icmp/tcp/http/dns/mtu/tcpscan> [args]

Global Options

• -r: Enable Recording Save the test results to a CSV file for future analysis.

• -p <number>: Rows Displayed Specify the number of rows displayed in the terminal during live tests. Default is 10.

ICMP Sub-Command (required privilege mode in Linux)

ICMP Options

• -c: ICMP Ping Count
  Number of ICMP ping requests to send. Default is 0, which means it will run non-stop until interrupted with Ctrl+C.

• -d: ICMP Ping Do Not Fragment*
  Sets the "Do Not Fragment" flag in the ICMP request. Default is false.

• -h: Help
  Display help information for the icmp subcommand.

• -i: ICMP Ping Interval
  Interval between ICMP ping requests in seconds. Default is 1 second.

• -s: ICMP Ping Payload Size
  Size of the ICMP ping payload in bytes. Default is 32 bytes. Total IP Packet size = IP Header (20 bytes) + ICMP Header (8 bytes) + Payload Size (specificed with '-s') Example: If Payload Size is 1472, the IP Packet size is 1500 bytes (20 + 8 + 1472)

• -t: ICMP Ping Timeout
  Timeout for each ICMP ping request in seconds. Default is 4 seconds.

💻 Example 1: ICMP continuous ping to "google.com" with recording enabled

nt -r icmp google.com

💻 Example 2: ICMP ping to "10.2.3.10" with count: 10, interval: 2 sec, payload 48 bytes

nt icmp -c 10 -i 2 -s 48 10.2.3.10

TCP Sub-Command

TCP Options

• -c: TCP Ping Count
  Number of TCP ping requests to send. Default is 0, which means it will run non-stop until interrupted with Ctrl+C.

• -h: Help
  Display help information for the tcp subcommand.

• -i: TCP Ping Interval
  Interval between TCP ping requests in seconds. Default is 1 second.

• -s: TCP Ping Payload Size
  Size of the TCP ping payload in bytes. Default is 0 bytes (no payload).

• -t: TCP Ping Timeout
  Timeout for each TCP ping request in seconds. Default is 4 seconds.

💻 Example 1: TCP ping to "google.com:443" with recording enabled

nt -r tcp google.com 443

💻 Example 2: TCP ping to "10.2.3.10:22" with count: 10 and interval: 2 sec

nt tcp -c 10 -i 2 10.2.3.10 22

HTTP Sub-Command

The http subcommand allows you to perform HTTP/HTTPS probing against a target host.
You can customize the HTTP method, expected status codes, and more.

Note:

• If custom port is not specificed, the test will use the default ports (HTTP 80, HTTPS 443).
• The default interval for HTTP Ping is 5 seconds.

HTTP Options

• -c: HTTP Ping Count
  Number of HTTP ping requests to send. Default is 0, which means it will run non-stop until interrupted with Ctrl+C.

• -h: Help
  Display help information for the http subcommand.

• -i: HTTP Ping Interval
  Interval between HTTP ping requests in seconds. Default is 5 seconds.

• -m: HTTP Ping Method
  HTTP request method to use (e.g., GET, POST). Default is "GET".

• -s, --statuscode : Expected HTTP status code(s). Accepts:

  • Shorthand ranges: 2xx, 3xx, 4xx, 5xx
  • Exact codes: 200, 301, 404, etc.

• -t: HTTP Ping Timeout
  Timeout for each HTTP ping request in seconds. Default is 4 seconds.

• -x, --proxy : HTTP or SOCKS5 Proxy
  Route all HTTP/HTTPS requests through a proxy.
  Supported schemes:

  • http:// or https:// (standard web proxies)
  • socks5:// or socks5h:// (SOCKS proxies)

  Examples:

  • No authentication:

    -x http://172.16.200.102:3128

  • With authentication:

    -x http://user01:S%40cretPass@172.16.200.102:3128

    Important: If your password contains special characters (@, :, /, %, etc.),
    you must URL-encode them. See the URL Encoding Reference for the full table of encodings. Example:
    • Actual password: S@cretPass
    • Encoded: S%40cretPass (because @ → %40)

💻 Example 1: HTTP ping to "https://google.com" with recording enabled (With default values: Port-443, Method-GET, Count-0, Interval-5s, Timeout-4s)

nt -r http https://google.com

💻 Example 2: HTTP ping to POST "http://10.2.3.10:8080/token" with count: 10 and interval: 2 sec

nt http -c 10 -i 2 -m POST http://10.2.3.10:8080/token

💻 Example 3: HTTP ping using the GET http://10.3.4.10:8080/health. The probe will be considered successful if the response status code is within the 200–299 range or exactly 301.

nt http -s 2xx -s 301 http://10.3.4.10:8080/health

💻 Example 4: Using a proxy with authentication. Perform HTTPS probe via an HTTP proxy at 172.16.200.102:3128, authenticating as user01 (password S@cretPass → encoded as S%40cretPass) and interval is 2 sec :

nt http -x http://user01:S%40cretPass@172.16.200.102:3128 -i 2 https://www.youtube.com

DNS Sub-Command

DNS Options

• -c: DNS Ping Count
  Number of DNS ping requests to send. Default is 0, which means it will run non-stop until interrupted with Ctrl+C.

• -h: Help
  Display help information for the dns subcommand.

• -i: DNS Ping Interval
  Interval between DNS ping requests in seconds. Default is 1 second.

• -o: DNS Ping Protocol Type
  Protocol to use for DNS queries (e.g., udp, tcp). Default is "udp".

• -t: DNS Ping Timeout
  Timeout for each DNS ping request in seconds. Default is 4 seconds.

💻 Example 1: DNS ping to "8.8.8.8" with query "google.com" and have recording enabled

nt -r dns 8.8.8.8 google.com

💻 Example 2: DNS ping to "4.2.2.2" with query "abc.com" with count: 10 and interval: 2 sec

nt dns -c 10 -i 2 4.2.2.2 abc.com

MTU Sub-Command

MTU Options

• -s: Ceiling Test Size
  The maximum MTU size to test, in bytes. Default is 1500 bytes.

• -h: Help
  Display help information for the mtu subcommand.

💻 Example 1: MTU check for destination google.com

nt mtu google.com

💻 Example 2: MTU check for destination 192.168.1.10 with user defined ceiling test size 9000 set (for Jumbo Frame enabled environment)

nt mtu -s 9000 192.168.1.10

TCP SCAN Sub-Command

Note:

• The maximum number of tested ports for each command run is 50.

TCP SCAN Options

• -t: **TCP Ping test Timeout **
  TCP Ping test Timeout (default: 4 sec) (default 4)

• -h: Help
  Display help information for the mtu subcommand.

💻 Example 1: TCP Scan to "10.123.1.10" for port "80, 443, 8080 & 1500-1505" with recording enabled

nt -r tcpscan 10.123.1.10 80 443 8080 1500-1505

💻 Example 2: TCP SCAN to "10.2.3.10" for port "22, 1522-1525 & 8433" with custom timeout: 5 sec

nt tcpscan -t 5 10.2.3.10 22 1522-1525 8433

Logging and Recording

When the -r option is enabled, all test results are saved to a CSV file in the same directory as the executable.

During the testing/recording process, the CSV file is named in the following format:

[recording...]_Record_<test type>_<test target host>_<timestamp>.csv

When the testing/recording is completed, the file name will be like this:

Record_<test type>_<test target host>_<timestamp>.csv

📌 Note:

During testing/recording, the file name will be prefixed with "[recording...]_". Please DO NOT open this CSV file at that time, as doing so will prevent test records from being saved to the file and will interrupt the test process.

• Example: Record_icmp_google.com_20211012T101530.csv

The CSV file captures the detailed test results based on the test type.

License

This project is licensed under the MIT License.

Contact

• Email: dennis.jian@packetstreams.net
• GitHub: djian01