Testing port connectivity

Question 1

how would I test connectivity on windows

Answer 1

Test-NetConnection

Question 2

How would I test port connectivity on Linux and mac

Answer 2

netcat

Question 3

What tool can we run through the command nc, and has two mandatory arguments, a host and a port?

Answer 3

Netcat

Question 4

What happens if you run:
nc google.com 80

Answer 4

it will try to establish a connection on port 80 to google.com.

Question 5

What happens if the nc connection fails?

Answer 5

the command will exit

Question 6

What happens if the nc command succeeds?

Answer 6

you see a blinking cursor waiting for more input.

Question 7

This is a way for you to actually send application layer dat to the listening service from your own keyboard.

Answer 7

the blinking cursor after an nc command succeeds.

Question 8

What command can I issue if I’m only curious about the status of a port?

Answer 8

nc with the -z flag

Question 9

what does the -z flag stand for in nc?

Answer 9

zero input output mode

Question 10

what does the -v flag stand for?

Answer 10

verbose. Makes the command output useful to human eyes as opposed to non-verbose.

Question 11

what output type is best for usage and scripts?

Answer 11

non-verbose.

Question 12

What happens if I issue:
nc -z -v google.com 80

Answer 12

Connection to google.com 80 port [tcp/http] succeeded!

The command’s output will simply tell me if a connection to the port in question is possible or not.

Question 13

Test-NetConnection google.com
running test connection with only the host specified

Answer 13

It will default to using an ICMP echo request, like Ping does, but displays more data.

Question 14

What commmand result default displays data including the data link layer protocol being used, computer name, remote address, interface alias, sourceaddress, pingSucceeded, PingReplyDetails

Answer 14

Test-NetConnection

Question 15

How can I ask Test-NetConnection to test connectivity to a specific port?

Answer 15

Test-NetConnection -port

Question 16

what are tools used to test network connectivity and communication between devices?

Answer 16

Netcat (nc) for Linux and Macand Test-NetConnection for Windows

Question 17

What tools check port connectivity at the transport layer, which creates and manages communications in a network through connections?

Answer 17

Netcat and Test-NetConnection

Question 18

what stands for networking?

Answer 18

net

Question 19

what stands for concatenate, from unix?

Answer 19

cat

Question 20

what means to link things together in a chain or series?

Answer 20

concatenate, cat

Question 21

What command tries to establish a transmission control protocol connection to the host <google.com> on the port <port 80>?</google.com>

Answer 21

nc [options] <host> <port>
ex: nc google.com 80</port></host>

Question 22

in netcat, what can the host be?

Answer 22

a website or targeted IP address

Question 23

In netcat, what can the port be?

Answer 23

a specific port or range of port numbers

Question 24

what command tells netcat to open a user datagram protocol (udp) connection, instead of a TCP connection?

Answer 24

nc -u <host> <port></port></host>

Question 25

Why what I need to use UDP ?

Answer 25

speed or efficiency purposes

Question 26

what command stands for zero input/ output and tells netcat to scan for open ports?

Answer 26

nc -z

Question 27

what netcat flag what I used to scan for unneeded services that could be listening into a network without sending any data to them? This can be combined with using a range of port numbers instead of a single port

Answer 27

nc -z

Question 27

what netcat command stands for verbose and gives extended output text important for debugging and troubleshooting

Answer 27

nc -v

Question 28

what command would I run if I want a scan looking for listening devices that will return lists of port and statuses on the network or website being scanned?

Answer 28

nc -v

Question 29

what stands for very verbose and gives more output text than just verbose

Answer 29

nc -vv

Question 30

what would I use if I've asked for a very detailed report of all ports and their statuses within the company network to get robust information on all ports and their statuses

Answer 30

nc -vv

Question 31

refers to a local port for a connection. Some protocols require specific source port to work properly, this lets you specify what port to connect from

Answer 31

nc -p

Question 32

executes a program after connection established. this option is not supported by all versions of netcat, but you can also use standard unix command line pipelines to pass network input two or from other programs

Answer 32

nc -e

Question 33

prevents domain name server lookup. use this when you have an IP address and numeric port to use for the connection and you want to avoid the overhead of domain name server, DNS, or if it is not working properly

Answer 33

nc -n

Question 34

if I want to evaluate a network for open doors a weak connections that would allow someone to hack into the network what can I run to determine if a connection to the port 80 is possible to google?

Answer 34

nc -v -z google.com 80

Question 35

command test paying connectivity and displays diagnostic information for a connection from the host on the selected port

Answer 35

Test-NetConnection

Question 35

what command, used in powershell, is case sensitive?

Answer 35

Test-NetConnection

Question 36

we command will I use of data transfer on the network is moving very slowly so I want to check the quality of the connection and view details about it?

Answer 36

Test-NetConnection -InformationLevel "Detailed"

Question 36

Tests ping connectivity with detailed results

Answer 36

Test-NetConnection -InformationLevel "Detailed"

Question 37

Tests a connection to a remote host

Answer 37

Test-NetConnection -ComputerName [remote host]

Question 38

Tests TCP connectivity to a specific host in port. This can be combined with the display detailed results option example: PS C:\> Test-NetConnection -ComputerName www.google.com -Port 80 -InformationLevel Detailed

Answer 38

Test-NetConnection -ComputerName [remote host] -Port [port number]

Question 39

Performs root diagnostics to connect to a remote host. This can require administrator privileges so you may have to run your powershell window as administrator

Answer 39

Test-NetConnection -ComputerName [remote host] -DiagnoseRouting

Question 40

Performs root diagnostics to connect or remote hosts with routing constraints. example: an employees having trouble connecting to a specific website from their computer, but other sites are loading fine. I can track connecting to the site directly with this:

Answer 40

Test-NetConnection -ComputerName www.example.com -Port 80 -InformationLevel Detailed Test-NetConnection -ComputerName [remote host] -constrainInterface [interface number] -DiagnoseRouting -InformationLevel "Detailed"