nt

nt (Net Test)

nt is a Swiss Army knife 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.

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.

• -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 icmp -c 10 -i 2 -s 48 10.2.3.10

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: 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

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".

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

Example 1: HTTP ping to POST "http://10.2.3.10:8080/token" with 2-second interval.

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

Example 2: HTTP continuous ping to "https://google.com".

nt -r http https://google.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: DNS ping to "4.2.2.2" with query "abc.com" with count: 10, interval: 2 sec and default protocol UDP

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 and custom interval: 2 sec

nt tcpscan -t 5 -i 2 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. The CSV files are named using the format:

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

• 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