Command line for looking at specific port

Question

Is there a way to examine the status of a specific port from the Windows command line? I know I can use netstat to examine all ports but netstat is slow and looking at a specific port probably isn't.

Sacristy

netstat is only slow if you don't use the -n switch, which means it has to do lots of DNS lookups. – Muscat

Answer 1

Here is the easy solution of port finding...

In cmd:

netstat -na | find "8080"

In bash:

netstat -na | grep "8080"

In PowerShell:

netstat -na | Select-String "8080"

Safe

How to use this command? I want to know this port number is working or not link:- [link]( https://.localhost:9043/ibm/console/login.do) – Malchus

Also worth mentioning the -o flag (i.e. -nao here) to include the PID of the process using the port. – Tisman

if you have any other used port which has "8080" then it will also be grabbed. For example 98080 or 78080 and so on – Movable

@Movable As other answers have pointed out, prefixing the port number you are a concerned about with a colon reduces (but does not necessarily eliminate) the possibility of getting false positives. So searching for ":8080" is better than searching for "8080". – Fibrilliform

Answer 2

You can use the netstat combined with the -np flags and a pipe to the find or findstr commands.

Basic Usage is as such:

netstat -np <protocol> | find "port #"

So for example to check port 80 on TCP, you can do this: netstat -np TCP | find "80" Which ends up giving the following kind of output:

TCP    192.168.0.105:50466    64.34.119.101:80       ESTABLISHED
TCP    192.168.0.105:50496    64.34.119.101:80       ESTABLISHED

As you can see, this only shows the connections on port 80 for the TCP protocol.

Tippler

Answer 3

I use:

netstat –aon | find "<port number>"

here o represents process ID. now you can do whatever with the process ID. To terminate the process, for e.g., use:

taskkill /F /pid <process ID>

Reconnaissance

Answer 4

when I have problem with WAMP apache , I use this code for find which program is using port 80.

netstat -o -n -a | findstr 0.0:80

3068 is PID, so I can find it from task manager and stop that process.

Arid

Very nice, thanks a lot! Specially for TCP I use following: netstat -o -nap TCP | findstr 0.0:80 – Lepido

Answer 5

As noted elsewhere: use netstat, with appropriate switches, and then filter the results with find[str]

Most basic:

netstat -an | find ":N"

or

netstat -a -n | find ":N"

To find a foreign port you could use:

netstat -an | findstr ":N[^:]*$"

To find a local port you might use:

netstat -an | findstr ":N.*:[^:]*$"

Where N is the port number you are interested in.

-n ensures all ports will be numerical, i.e. not returned as translated to service names.

-a will ensure you search all connections (TCP, UDP, listening...)

In the find string you must include the colon, as the port qualifier, otherwise the number may match either local or foreign addresses.

You can further narrow narrow the search using other netstat switches as necessary...

Further reading (^0^)

netstat /?

find /?

findstr /?

Mesopause

Answer 6

netstat -a -n | find /c "10.240.199.9:8080"

it will give you number of sockets active on a specific IP and port(Server port number)

Psid

This is not working for windows power shell on windows 2012 R2 and received result as FIND: Parameter format not correct – Mancini

Answer 7

It will give you all active sockets on a specific IP:

netstat -an | find "172.20.1.166"

Palpitation

Answer 8

To improve upon @EndUzr's response:

To find a foreign port (IPv4 or IPv6) you can use:

netstat -an | findstr /r /c:":N [^:]*$"

To find a local port (IPv4 or IPv6) you can use:

netstat -an | findstr /r /c:":N *[^ ]*:[^ ]* "

Where N is the port number you are interested in. The "/r" switch tells it to process it as regexp. The "/c" switch allows findstr to include spaces within search strings instead of treating a space as a search string delimiter. This added space prevents longer ports being mistreated - for example, ":80" vs ":8080" and other port munging issues.

To list remote connections to the local RDP server, for example:

netstat -an | findstr /r /c:":3389 *[^ ]*:[^ ]*"

Or to see who is touching your DNS:

netstat -an | findstr /r /c:":53 *[^ ]*:[^ ]*"

If you want to exclude local-only ports you can use a series of exceptions with "/v" and escape characters with a backslash:

netstat -an | findstr /v "0.0.0.0 127.0.0.1 \[::\] \[::1\] \*\:\*" | findstr /r /c:":80 *[^ ]*:[^ ]*"

Thibaud

Answer 9

For Windows 8 User : Open Command Prompt, type netstat -an | find "your port number" , enter .

If reply comes like LISTENING then the port is in use, else it is free .

Dionysus

Answer 10

This will help you

netstat -atn | grep <port no>          # For tcp
netstat -aun | grep <port no>           # For udp
netstat -atun | grep <port no>          # For both

Knob

Answer 11

For port 80, the command would be : netstat -an | find "80" For port n, the command would be : netstat -an | find "n"

Here, netstat is the instruction to your machine

-a : Displays all connections and listening ports -n : Displays all address and instructions in numerical format (This is required because output from -a can contain machine names)

Then, a find command to "Pattern Match" the output of previous command.

Perspicuous

Answer 12

In RHEL 7, I use this command to filter several ports in LISTEN State:

sudo netstat -tulpn | grep LISTEN | egrep '(8080 |8082 |8083 | etc )'

Holograph

Answer 13

in linux： To find a foreign port you could use:

netstat -anp |grep port|awk '{ print $5 }' |grep port

To find a local port you might use:

netstat -anp |grep port|awk '{ print $4 }' |grep port

Barbrabarbuda

Answer 14

For exact match [windows command prompt]

netstat -aon | findstr "\<5000\>"

Polyp

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Answer 15

If you need to check several ports - the simplest way to do it use findstr with several strings for search:

findstr /C:":80 " /C:":443 " /C:":8080"

Spaces after the port numbers are important, without the space findstr will select everything which starts e.g. from ":80". In my case complete command looks like this:

netstat -an | findstr /C:":80 " /C:":443 " /C:":8080"

Erythrocytometer

Answer 16

For me below commands working to check specific port status

netstat -an | find ":8000"

netstat -aon | findstr ":8000"

Smasher

Answer 17

Use the lsof command "lsof -i tcp:port #", here is an example.

$ lsof -i tcp:1555 
COMMAND   PID USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
java    27330 john  121u  IPv4 36028819      0t0  TCP 10.10.10.1:58615->10.10.10.10:livelan (ESTABLISHED)
java    27330 john  201u  IPv4 36018833      0t0  TCP 10.10.10.1:58586->10.10.10.10:livelan (ESTABLISHED)
java    27330 john  264u  IPv4 36020018      0t0  TCP 10.10.10.1:58598->10.10.10.10:livelan (ESTABLISHED)
java    27330 john  312u  IPv4 36058194      0t0  TCP 10.10.10.1:58826->10.10.10.10:livelan (ESTABLISHED)

Ranjiv

Minus point because this is not a windows command. If it is available on windows there is no discussion on how to acquire it. – Afferent

Does not answer OP's question. -1. – Alexandra

Answer 18

This command will show all the ports and their destination address:

netstat -f 

Anderson

The request was to find out if a specific port was in use. – Afferent