Questions tagged [netstat]

analysis tool for statistics about active connections, open sockets, routing tables; in general the networking subsystem.

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1answer
2k views

Why is the 'foreign address' not IP address but something like this?

I never learned network programming and this kind of stuff properly. Only know very basic stuff like IP address and just a vague concept of what ports and TCP/IP are. Here, I connected to my lab's ...
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3answers
7k views

Command similar to netstat -np but grouped by state and PID?

Is there a command similar to netstat -np but grouped by state and PID? I'd like to know the current count of server connections in a particular state grouped by Programs. similar to, 102 squid ...
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3answers
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Why does SSH show protocol as tcp6 *and* tcp in netstat?

$ netstat -nat Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:80 0.0.0.0:...
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3answers
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How to determine eth0 gateway address when it is not the default gateway?

In my system I have eth0 (which may or may not be connected) and a modem on ppp0 (which always may be up or down). The the case where both interfaces are up and ppp0 is the default route, I'd like to ...
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3answers
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tcp6 in the output netstat

What does column 'tcp6' mean on output netstat? Please anyone explain the follow output of netstat: tcp6 0 0 dmz.local.net:www 5.140.235.6%14631:49964 ESTABLISHED 21393/apache2 What does tcp6 mean?
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2answers
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Iptables rule to allow only one port and block others

We have two apps running (on top of linux) and both communicates through port 42605. I wanted to quickly verify if this is the only port that's been used for communication between them. I tried below ...
0
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2answers
971 views

what process is listening on a given port

I have several problems: some process is attempting to send data and the firewall is rejecting it at the rate it is sending it out firewall logs flood the system (may need to rate-limit the logging) ...
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2answers
209 views

Find which ports a program access

I have a program that tries to connect to a server on start-up on a unknown port. I need to find out which port the program accesses to enable a ssh tunnel. I tried netstat but since the connection ...
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2answers
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netstat command doesn't work anymore on the new dedicated server

I was using the following command on my previous dedicated server with the same version of the FreeBSD installation: # uname -a FreeBSD 9.2-RELEASE FreeBSD 9.2-RELEASE #0 r255898: Thu Sep 26 22:50:31 ...
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1answer
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Accounting for /proc/net/dev reported traffic

I noticed that according to /proc/net/dev I am constantly receiving around 6Kb/s on my wireless usb interface. But I can't account for anything even close to that with the individual connections that ...
2
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2answers
5k views

Where are netstat's -t and -u flags documented?

I use the following command to find open ports on my servers: $ netstat -ntulp I've probably found that on some random website over the years. However, I cannot find where -t or -u are documented. ...
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1answer
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Understand netstat -i flgs

Can anyone explain for me what each option in Flg means? [root@apple ~]# netstat -i Kernel Interface table Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg eth0 ...
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2answers
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What does 0.0.0.0:* mean in netstat?

Could anyone explain the following output of netstat -plunt? udp 0 0 0.0.0.0:58262 **0.0.0.0:*** 1163/avahi-daemon: udp 0 0 0.0.0.0:17500 **0.0.0.0:***...
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0answers
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Command for finding open ports

On my linux servers I have this alias set: alias ns="sudo lsof -Pi|grep -v ESTABL|grep -v CLOSED|grep -v -e '->' | tr -s ' ' '\t' | awk '{print $3 "\t" $8 "\t" $5 "\t" $9 "\t" $1}'| column -t|...
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5answers
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Finding the PID of the process using a specific port?

I am installing hadoop on my Ubuntu system. When I start it, it reports that port 9000 is busy. I used: netstat -nlp|grep 9000 to see if such a port exists and I got this: tcp 0 0 ...
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2answers
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OS X: how to keep the computer from sleeping during a http connection

An application I use downloads data from a specific server, and I need it to sleep after the download has finished and the socket is closed. However downloads take place at random days, the app that ...
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2answers
5k views

How to use netstat command

My question is what does it mean to LISTEN or ACCEPT on a port as it relates to my example? Example: I have a tomcat server, and It will use port 8080. I want to make sure that port is available for ...
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2answers
7k views

Open a port in my CentOS

I'm trying top open a port on my CentOS machine: I edit the /etc/sysconfig/iptables file and add my rule: -A INPUT -p TCP -m state --state NEW -m tcp --dport 143 -j ACCEPT Then I restart the ...
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2answers
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Why doesn't my client IP address appear in the netstat output?

My client is a MS Excel plug-in running on my laptop (client_machine1) that connects to a Solaris server (server1) to request some WebLogic Application running on port 28080. bash-3.2$ set | grep ...
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1answer
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why ss(8) understands listening UDP ports differently than netstat(8)?

If I execute ss -lu in order to view all the listening UDP sockets, then none of the sockets are displayed. If I execute ss -au, which lists all(both listening and non-listening) UDP sockets, then "...
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4answers
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How do I know what service is running on a particular port in linux? [duplicate]

I am trying to run weblogic server on my linux machine and I am getting the following error : ERROR: transport error 202: bind failed: Address already in use ERROR: JDWP Transport dt_socket failed to ...
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14answers
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What's the easiest way to find an unused local port?

What's the easiest way to find an unused local port? Currently I'm using something similar to this: port=$RANDOM quit=0 while [ "$quit" -ne 1 ]; do netstat -a | grep $port >> /dev/null if ...
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4answers
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How to check that a daemon is listening on what interface?

Ex.: an sshd is configured to only listen on wlan0. So. Besides checking the sshd_config how can I check that a daemon is listening on what inerface? netstat can do it? how? (OS: openwrt or scientific ...
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5answers
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How to do an if statement from the result of an executed command

I am trying to do an IF statement from the output of an executed commmand. Here is how I am trying to do it, but it doesn't work. Does anyone know the right way to do this? if [ "`netstat -lnp | ...
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1answer
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Have netstat not display port numbers for foreign address

I would like to get netstat to not display port numbers on the foreign address so I can run some statistics on it. This is for a FreeBSD system. The following is a example of the output. <root&...
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1answer
1k views

Netstat shows programs running on different ports then they should

I have some code I'm testing. Program A listens on a predefined socket for program B to connect to and for my testing I'm running 32 instances of the programs A and B. I've written my script to tell ...
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3answers
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How can I know the process name which is opening a tcp port?

I have two linux servers. Let's say they are C and S. C is client of S On my S machine, I type. $ netstat -an | grep ESTABLISHED tcp 0 0 192.168.1.220:3306 C:57010 ...
2
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1answer
848 views

Information about the 1630/master app

When I run $ sudo netstat -a --programs | grep LISTENING | grep 1630 I will get this output. Do you know what good are processes running under this app name? Why they are running on my system and if ...
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3answers
371 views

How can I identify processes that use network facilities, and can they be killed?

In the output of netstat -a | grep LISTEN there are usually a lot of processes. How (where) can I find out information about them, what is their purpose in the system and if I can kill them? Which ...
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4answers
8k views

How to list all unique ip address currently connected to a specific port?

Say I want to know how many unique clients are connected to port 5222 on a server. Can you find a way better/faster/stronger than this? netstat -nt | grep ':5222.*ESTABLISHED' | awk '{ print $5 }' \ ...
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2answers
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Per Socket network Buffer queues utilization

Is there a way to get a per-socket send and receive Queues utilization on Solaris similar to the way that Linux' netstat displays it? Example on Linux: Proto Recv-Q Send-Q Local Address ...
22
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4answers
29k views

Logging outgoing connections as they happen

Is there a way to log to file all the outgoing connections that a process creates? I am aware of netstat but that seems to be more of a snapshot of a point in time rather than something that runs and ...
2
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3answers
884 views

VPN and gateway problems

I've got a corporate VPN, which I use to access the Internet. When it's on, I cannot reach the servers inside the corporate network anymore, so I think there are some problems with the gateway setup. ...
4
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3answers
11k views

Source code of netstat

Can I view the source code of netstat on my Linux machine?
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5answers
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Under AIX, how can I get the full path of a program bound to a port?

Under Linux I can use netstat -tulpnw and ps, like so: # netstat -tulpnw | grep :53 tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1482/named udp ...