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Questions tagged [netstat]

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

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

322 questions
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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 HttpStubStatusModule installed first, e.g. Active…
Howard
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In the output for netstat what does the [::] mean?

In the results for netstat what does the [::] mean? example [::]:ssh [::]:* LISTEN
Ric
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3 answers

How to catch DNS request using 'netstat' in Unix

I am working in a bank where 'netcat' is not there. I am having problem wherein one DNS server of the two going down is causing impact. In order to troubleshoot, I need to catch the request (incoming and outgoing) from the DNS clients (AIX). How can…
Biman Roy
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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 ESTABLISHED So, as per the man page, I enter: $…
Charles Salvia
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1 answer

HTTPD listening in IPv6, according netstat, but reacheable in IPv4

Using Openstack, I have a Web GUI (horizon) hosted on my server (HTTPS). When I do a netstat -lt | grep https, I have: tcp6 0 0 [::]:https [::]:* LISTEN With lsof -i :443, I have: COMMAND PID USER FD …
Antonin M.
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Where are my TIME_WAITs on Mac OS X?

No TIME_WAITs on Mac OS X Normally, when a TCP connection is closed, the socket on the side where close() is called first is left in the TIME_WAIT state. When one of the peers is a Mac OS X (Lion) machine, no TIME_WAIT is listed by netstat -an on…
mgd
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2 answers

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 returning payloads of ~450kb. There's also an http…
hellvinz
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1 answer

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 and trying to open one more socket when it…
Luke
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9
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Showing date/time in netstat

Is it possible to have netstat show the date/time the connection was established? Is this information even stored anywhere in Linux?
kernelpanic
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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 and how should I troubleshoot it?
user20414
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Get number of TCP established connections

On a Linux server one can use netstat -tan | grep ESTABLISHED| wc -l but this will not work on a high load server with watch -n1. Such approach works fine if the server is not very busy or the monitoring interval is big enough. But what can be…
Vinicius Tinti
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1 answer

Avoid TIME_WAIT connections

When I use netstat command it shows.. tcp 0 0 localhost:18056 localhost:mysql TIME_WAIT tcp 0 0 localhost:16683 localhost:mysql TIME_WAIT tcp 0 0 localhost:16701 …
Himanshu Matta
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7
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1 answer

Port 80 being used by Microsoft-HTTPAPI/2.0

It's been quite a few days that port is being used by some strange process which i don't know Initially i thought it's related to SQL Server. I tried stopping all the services which starts from SQL :). But it's still the same. To determine the…
kgthenerd
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3 answers

TIME_WAIT connections not being cleaned up after timeout period expires

I am stress testing one of my servers by hitting it with a constant stream of new network connections, the tcp_fin_timeout is set to 60, so if I send a constant stream of something like 100 requests per second, I would expect to see a rolling…
Mark D
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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 "connections reset due to unexpected data". The value…
Malcolm Box
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