netstat is a tool for viewing active network connections, listeners and sockets.

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0
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1answer
29 views

there is empty ips in netstat

I have installed ddos deflate on my sever (centos6.5 64bit) and in server mailbox I see that ddos deflate has been blacklisted empty Ip. and when I run this command on ssh I see: netstat -ntu | awk ...
1
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1answer
687 views

How to reset netstat -e counters

I would like to reset netstat -e counters. How can I do it? Renewing the network interface may reset these counters, but it is NOT an option - the networking must not be interrupted. My OS is ...
8
votes
6answers
5k views

netstat shows a listening port with no pid but lsof does not

This question is similar to Network port open, but no process attached? I've tried everything from there, reviewed the logs, etc... and can't find anything. My netstat shows a TCP listening port and ...
3
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7answers
18k views

Port 80 is being used by SYSTEM (PID 4), what is that?

I am trying to use port 80 for my application server, but when I perform "netstat -aon" I get TCP 0.0.0.0:80 0.0.0.0:0 LISTENING 4 When I look up the process in ...
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2answers
38 views

How to find the count of Apache workers' at a given point for shared IPs?

One can find the number of Apache workers an IP address is consuming at an instantaneous point in time by executing: netstat -pantu | grep :80 |sort | uniq -c |grep <IP_HERE, eg: 192.168> | wc ...
3
votes
2answers
136 views

After kill -9 process won't disappear and port is still bound

We have a Java server application running on Mac OS X. Occasionally this application has become unresponsive, and we have resorted to killing it with kill -9. However, the process doesn't disappear; ...
5
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4answers
10k views

Running lsof -i shows a lot of connections in CLOSE_WAIT ? Should I worry

So I am running lsof -i | wc -l periodically and it is telling me that out of 420 lines, between 240 and 255 are in CLOSE_WAIT state. How does TCP connections enter this state ? Should I be worried ...
0
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2answers
69 views

What are records in 'netstat' command are when using logstash?

I use logstash with embedded elasticsearch. My logstash config looks like the following: output { tdout { debug => true debug_format => "json"} elasticsearch { embedded => true ...
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2answers
113 views

Can I find the list of ports being listened by a process ordered by the time of opening?

I know I can see the list of open ports using the lsof command. I am trying to view the results ordered by timestamp of listening. The process opens multiple (~6) ports and I suspect the order of ...
-3
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2answers
44 views

How to get the number of current connections to an external web service [closed]

My application makes many requests in a day to a webservice (say 172.20.20.20:11111) on a different server. I would like to know how I can count the number of connections that are established (the ...
0
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2answers
54 views

netstat brought up strange ip

I just ran netstat -vatn and found there was a connection ESTABLISHED on :22 from my ip and another unknown ip. Moments later I ran it again and found the connection was gone. I have a default ...
1
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0answers
220 views

What does “connections reset due to unexpected data” in netstat -s mean

I'm running a memcached server under heavy load from multiple web servers. While investigating some odd app level behaviour, we spotted that netstat -s on the memcached box was showing a lot of ...
5
votes
1answer
515 views

Why is rpc.lockd obscured from netstat/lsof output?

Prologue: On a number of machines, which happen to act as NFS clients, netstat reports two ports that are open with no PID listed for an associated daemon. Ordinarily this might be a bit concerning. ...
57
votes
4answers
59k views

What's the difference between ip address 0.0.0.0 and 127.0.0.1?

I do know that 127.0.0.1 ~ 127.255.255.254 are the loopback IP addresses for most modern operating systems and we could use these IP addresses to refer to our own computer. But what's 0.0.0.0? It ...
2
votes
1answer
123 views

Netstat hangs: why?

Sometimes (not too often at all) when I type "netstat", it takes over 5 seconds to return. While other times is instantaneous. I have been observing this for weeks on my server (CentOS 6.4), but I ...
0
votes
1answer
464 views

How does netstat get a hostname from IP while nslookup & nblookup fail every time?

In Windows Server 2003, when I run netstat with no flags, it takes much longer than netstat -n to return results. I realize this is because it has to perform reverse lookups by IP address to get the ...
1
vote
1answer
158 views

Lots of TIME_WAIT from same IP address

I've seen a lot of questions with people concerned about lots of TIME_WAITs in netstat. I'm having a similar problem but all the TIME_WAITs are coming from the same IP address. I get over 200 of the ...
0
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1answer
104 views

Port scanning from localhost

I see lot of tcp connections on different ports on my server with 'TIME_WAIT' status. Just simple port scan, but i cant see ip address of this bastard because connections is going from my nginx. Can ...
0
votes
1answer
57 views

How to find full process arguments and associated listening ports?

I can execute netstat -atulpn | grep java to find all Java processes with their accompanying ports, which is great, however I would like to also have the processes full execution arguments also shown. ...
2
votes
1answer
95 views

Find number of TCP bytes transmitted

I have rhel4 and rhel6 hosts. I can use netstat -s to see information on the number of segments sent/received. I can use ifconfig to see the number of bytes sent/received on a given interface (for ...
0
votes
1answer
346 views

UDP port appears to be in use but is not shown in netstat or TCPView

I've encountered some strange behavior I don't understand. I'm installing software on a Windows 2003 Server. This software needs to bind to a specific UDP port an all TCP addresses in order to listen ...
1
vote
2answers
200 views

Why is netstat -n different between Solaris and Linux and how can I make it the same?

When I run netstat -n on Solaris I get different results from netstat -n on Linux, even though according to the manual pages in Solaris and Linux the -n flag should do the same thing. My question: ...
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2answers
67 views

Linux: Find amount of “active” connections on one port

i need to monitor how many users are actively connected to one port on debian. I know i can do it with command netstat -na |grep $port |grep ESTABLISHED |wc -l which really gives me result - a ...
9
votes
4answers
21k views

How do I make cURL use keepalive from the command line?

I'm trying to verify that HTTP persistent connections are being used during communication with a Tomcat webserver I've got running. Currently, I can retrieve a resource on my server from a browser ...
2
votes
1answer
97 views

Cannot install net-tools on Red Hat Linux

The isolated networking lab is running Red Hat Linux 9 (Shrike). We still use this "ancient" release, because given the simplicity of the protocols examined, it is sufficient. In addition, because of ...
0
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0answers
57 views

netstat ? Huge buffer build-up

we are seeing the following: The netstat line which shows the buildup: 10:51:34|tcp 4294967258 0 192.20.1.228:53824 192.20.1.228:2500 ESTABLISHED The netstat command used to generate the ...
0
votes
1answer
148 views

Application Unable connect Remote Server. FIREWALL Issue

Developing a C# Application that uses an WDSL/SOAP service and connects to a server via port 443 I know it is a Firewall Windows 2008 Server issue. Because when I disable it, it works perfectly. ...
0
votes
1answer
237 views

Random TCP Resets

We got randomly TCP "reset" error when we send request to remote server. Log from remote server Cisco TCP Connection Terminated,Nov 05 14:43:39 EST: %ASA-session-6-302014: Teardown TCP connection ...
0
votes
1answer
72 views

Strange ports on default install of W7

I have a base new install of windows 7, and when I went to look for something else I saw the attached netstat output. What concerns me is that this is Windows + Truecrypt + drivers, nothing else ...
0
votes
1answer
216 views

how to display netstat output on nagios

Can you please tell me how to monitor an established connection (on a specified port) in a windows machine from nagios (centOS) here an example (output of netstat): Proto Local Address ...
0
votes
1answer
92 views

IP routing Solaris 9 access the internet from local network

I am trying to configure the NICS on the Solaris Sparc server. My problem lies in getting out to the "Internet" from the local network. I have requested the NIC to receive a DHCP server address ...
2
votes
2answers
139 views

Determine from where is “sh” being run under apache www-data user using using PF or NETSTAT [duplicate]

I am working with a compromised Ubuntu 8.04 Plesk 9.5.4 server. It seems that a script on the server is continuously doing reverse lookups to random IPs on the Internet. I first spotted it during by ...
0
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0answers
72 views

How can I use “show netstat” on a Sonicwall NSA 2400 correctly?

I have a SonicWALL NSA 2400 and I would like to view statistics on open connections. It seems there is a netstat command available via the serial console but It doesn't seem to work correctly. Once ...
4
votes
2answers
516 views

How found suspect connection in a netstat output?

It seems some ssh brute force are outgoing from my debian 7.1. I'm searching how to find the source of these brute force. I'm searching in netstat output, but how can i identify trace of this hack ? ...
1
vote
2answers
75 views

How to map an ephemeral port to a pid?

I have a RHEL server with several apps on it and I am attempting to figure out which one of them is making calls to an external web service. I have TCP dumps that show the calls being made and through ...
0
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0answers
195 views

What does given filed mean in netstat -s on Linux

I am analyzing the the output of netstat -s and wanted to know what "input ICMP message failed" is meant for ,below is output of netstat -s Icmp: 643 ICMP messages received 0 input ICMP ...
3
votes
3answers
571 views

python reports socket in use, netstat and others claim its not

We have a strange socket issue with a RHES3 box: Python 2.4.1 (#1, Jul 5 2005, 19:17:11) [GCC 3.2.3 20030502 (Red Hat Linux 3.2.3-52)] Type "help", "copyright", "credits" or "license" for more ...
4
votes
2answers
3k views

lots of packets pruned and packets collapsed because of socket buffer low/overrun

i've set up a test machine (debian squeeze 2.6.32 on a linode 2048 machine) that interact with an api that returns large chunks of json. It calls the API 3000/minutes asynchronously, the api is ...
1
vote
1answer
353 views

Check nginx active connection without HttpStubStatusModule

We want to check the number of active connections without the module HttpStubStatusModule being installed. What would be the equivalent Linux command? As a base line, we test on a machine with ...
0
votes
1answer
143 views

What's the meaning of `netstat -i` flags

When I run netstat -i in Linux, I get outputs like: Kernel Interface table Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg eth0 1500 0 0 0 0 0 ...
5
votes
3answers
5k views

How to kill a TCP connection using tcpkill utility

I'm trying to kill an ESTABLISHED TCP connection using tcpkill. The connection is an open HTTPS connection. It appears on netstat as: tcp 0 0 X.X.X.X:55601 X.X.X.X:https ...
0
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2answers
355 views

HTTP attack - Too many connections & TIME_WAIT

I am running CentOS 6 with http -2.2.15 Going under HTTP attack, i can see many http process running. > netstat -nat | awk '{print $6}' | sort | uniq -c | sort -n > 1 established) > ...
1
vote
2answers
610 views

Debian iptables, netstate. DDOS? [duplicate]

My server has been timing out and crashing lately. I ran this command: netstat -anp |grep 'tcp\|udp' | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n Check the picture for result. ...
0
votes
1answer
343 views

Netstat doesn't work on FreeBSD by php function exec()

In my php-app I need the list of all IP's connected on port 80. I've chosen to do it this way: <?php $ips = exec("netstat -an |grep 'tcp\|udp' | awk '{print $5}' | cut -d: -f1 | sort | uniq ...
2
votes
1answer
1k views

Too many established connections left open

I have a (probably quite old) CentOS 4.5 server with a custom java application running inside. I found the application was crashing after some running time and found it was handling 1024 connections ...
0
votes
1answer
85 views

Reverse-resolved address ending with .bng?

I routinely check netstat --tcp when ssh'ed into my server, but today found an odd hyphenated address format that I haven't seen before: Proto Recv Sent Local Address Foreign Address ...
0
votes
1answer
166 views

Apache2 many CLOSE_WAIT. LAMP. Locating the issue

I've got a LAMP setup running and I seem to have many CLOSE_WAIT connections for apache2 program when I netstat (several hundred). This eventually causes my apache to become unresponsive. Bellow is ...
0
votes
1answer
288 views

How to check if sockets are sending/receiving data on linux?

I often have to debug processes which involve a server client tcp connection. I'd like to check, during times where a client might seem stuck, whether the server is sending it data or not. I can use: ...
0
votes
1answer
185 views

Find IP addresses with most connections on system

I am currently experiencing some attacks on my OpenVZ server (CentOS 6.3 64bit), which is saturating the public ethernet interface (currently accessing SSH via the private interface). Is it possible ...
3
votes
1answer
94 views

What is a good way to determine a server's connection usage?

Trying to figure out where my system's connections are being used (i.e. how many connections belong to what processes - could even be filtered by some expression through grep, if it applies). The ...