Questions tagged [netstat]
netstat is a tool for viewing active network connections, listeners and sockets.
304
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Dovecot claims ports are in use, netstat disagrees
Attempting to start dovecot gives me this:
Apr 28 13:37:00 master: Error: service(pop3-login): listen(*, 110) failed: Address already in use
Apr 28 13:37:00 master: Error: service(pop3-login): listen(*...
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0
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Can SSH but cannot connect via HTTP
I am trying to set up a web application on my server. I can ssh to the server but when I connect via any browser (using IP or URL) I get no response. Running sudo netstat -tulpn | grep LISTEN gives ...
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2
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netstat reports UDP ports with no owning process
When I run netstat -avp udp I get a slowly growing number of ports. It grows about 100 an hour but the rate varies considerably.
When I close the process, the ports do not disappear from the list. ...
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1
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Exim established many connections to strange ips
I installed VestaCP and used their mail server for my domain mails. But when I run netstat on my server,it shows some strange connections. There are no problems with my mail server until now, I just ...
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0
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Kernel TCP tuning for buffer overrun and packet collapse
We have a Nginx+Ruby application where the data between Nginx and the application are interfaced through a socket.
As part of performance improvement, when we analyzed the netstat statistics on the ...
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0
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Showing all http connections in vm instance
I have a Google Cloud VM instance running Debian and a dockerized Apache httpd inside. I'm trying to count all the http connections in the machine.
I run this:
for i in {1..1000}; do netstat -at | wc -...
google-cloud-platform
2
votes
1
answer
2k
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cURL can connect to localhost but browser cannot
My system is Win10 with WSL2, I ran a gogs docker container (from ubuntu in WSL):
83b2a8833235 gogs/gogs "/app/gogs/docker/st…" 17 minutes ago Up 17 minutes 0....
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New netstat Ubuntu 20.10
I have been using netstat 1.42 without any problem but yesterday I installed a fresh VPS and when I try to set commands netstat does not show anything.
I use this command to see all active TCP ...
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1
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Want to enable Windows Server firewall - how to know what ports to open
For added security, we're thinking of enabling the firewalls on our 2016 and 2019 servers. Currently, they're all behind our edge router/firewall, and every server has its firewall disabled. Sometimes,...
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Ngnix Closes The Connection Doesn't Return 301
struggling to get my hosts to work on port 80/HTTP and redirect to HTTPS. Discovered this when I gave out a URL and they said it didn't work but noticed a direct link to the site did work. I've done ...
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0
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Why two TCP connections to mysql server?
When I connect to a mysql server via a client, it seems to create two new TCP connections each time, for example doing:
$ netstat -a |grep mysql
# tcp4 0 0 lmy.att.64710 ec2-54-00.mysql ...
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OpenVPN Access Server has a lot of listening ports
I have setup OpenVPN Access Server for a small private cloud network.
It works great, but I am wondering about all these 900 ports showing up in netstat from part of the system called openvpn-openss. ...
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1
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0
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Get information about socket of unknown domain
The output of lsof (revision: 4.87) on centos 7.8.2003 shows:
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
java 30858 xxxx 841u sock 0,7 ...
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netstat shows a listening port with no pid and can't find pid with rpcinfo and ss and lsof
I tried bind nc on port 41120, but it said port has already been used. So I want to find out which process binded this port and if I can kill it. I executed netstat -taupen| grep 41120 and it shows ...
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Netstat port status
How can I see all ports and their status on my pc using netsat? (All 2^16 ports) And how can I list apps that have an open port in transport layer of my computer with application name and it's port? ...
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what are the options to close manual the port correctly or release the port on rhel machines?
we have redhat 7.5 server
we are suspect that port 50070 not closed correctly by the service , ( we check by netstat and PID not found ) but from the log we can see that port is in use
so we try to do ...
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1
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SAMBA netstat local address 0.0.0.0
Trying to run samba AD DC but I'm stuck. After created domain provision, I defined resolv.conf:
cat /etc/resolv.conf
nameserver 10.99.0.30
search example.com
Service running:
samba-ad-dc.service - ...
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1
answer
114
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New and Unknown Netstat Entries
OS = Debian 10.
When I run netstat -natp, I have two unidentified entries which are concerning.
tcp 0 0 127.0.0.1:6379 0.0.0.0:* LISTEN 24310/redis-server
...
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1
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Proxy service only responding on some IP addresses (others suck on SYN_RECV)
I have a server using a proxy service (WAF etc) which forwards packets to my server.
I can see established SSL conenctions from all proxy netstat -an and the rest stuck in SYN_RECV:
tcp 0 ...
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1
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DDOS manual mitigation using command netstat. How to determine real attackers?
When my server is slow, I have been told to run this command and check if someone is making a request of SYN_RECV to slow down my server:
netstat -npt | grep SYN_RECV | awk '{print $5}' | grep -Eo '(...
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1
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netstat how to exclude localhost from the result when using grep
When I run this command in my terminal:
netstat -an | egrep ":80|:443" | sort
I got this following output:
tcp 0 0 172.104.10.125:48310 172.104.10.125:8081 TIME_WAIT
tcp ...
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3
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How can a server accept incoming traffic to port 443 if it isn't listed in netstat?
I have a server that is currently accepting HTTPS requests and the only thing that shows with netstat -plnt is this:
elijahlynn@web:~$ sudo netstat -plnt
Active Internet connections (only servers)
...
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0
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471
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Find the process listening on a port (not showing in lsof)
Update:
The port was opened by NFS. I figured this out by configuring NFS to listen on a known port.
Using Ubuntu 18.04
I want to know which process or kernel function listens on UDP port 38637.
I ...
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1
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173
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Linux service is listening and responding on ports it wasn't assigned and that don't show up in netstat
I have an Amazon Linux 1 instance that was created from a Solarwinds DPA AMI. I created this around 2 years ago. It is possible I did something weird back then to make this happen.
Today, I upgraded ...
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1
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88
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Huge amount of imap-login netstat
When I run a netstat -plantu I have a huge amount of ESTABLISHED imap-login, perhaps 50 or 60 connection.
Some connections have in column Send-Q a big number like 3211206 or 114636 for example, and ...
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3
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5k
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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 ...
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0
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112
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List active sessions from tun interface
I'm running CentOS and have a tun interface with IP subnet 10.0.0.0/24 attached for "users".
Is it possible to list current active sessions with netstat, ss or similar?
Ex. netstat something:
tun-...
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0
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380
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Iptables rule for limiting connections per ip
I'm usig the following iptable rule to limit the amount of simultaneous connections to 1 connection per ip, on port 4387.
/sbin/iptables -A INPUT -p tcp --syn --dport 3387 -m connlimit --connlimit-...
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1
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378
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Using netsh or netstat (or other native tool) to display UDP traffic to Windows server from given host
We have a Windows server that we suspect is not receiving UDP traffic from a Linux server. We've been able to establish, using tcpdump, that the Linux server is sending UDP traffic and we would like ...
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1
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Filter ss process output without using grep
ss -p can give the process name, process id (PID) and the file descriptor associated with the connection.
Example: ss -tuanp
[...]
tcp ESTAB 0 0 x.x.x.x:59594 x.x.x.x:993 users:(("...
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IP Show on netstat -n
Could someone with more experience help me in this?
I have an idea in my head and i've been trying to put it into practice.
I have two machines, one where the application is hosted (I'll call it "...
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0
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Duplicate Local Port in Virtual Guest's /proc/net/tcp
I'd like to understand the following two entries in my VirtualBox's guest's /proc/net/tcp:
6: 00000000:18EB 00000000:0000 0A 00000000:00000000 00:00000000 00000000 0 0 9581 1 ...
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1
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Network Policy Server + RADIUS not listening on any ports for Windows Server 2019
I must be missing something basic - is there some "master" switch for enabling Network Policy Server? It's not listening on any of the RADIUS ports. Detail:
Trying to setup Windows Server 2019 as a ...
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1
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47
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Local webserver with long response time
We have set up a new infrastructure and all our Laptops/PCs have a the same error:
When trying to open a website from a local webserver, it takes between 10 and 30 seconds. During this time it does ...
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2
answers
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What address should the client connect the socket to [duplicate]
SOLVED
SOLUTION: I tried the connection with a little server program and it works perfectly fine. I could connected it to 10.195.5.53. My problem is within the software of my client program it has ...
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1
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Netstat and ss doesn't see connection
I'm trying to find which application running on Kubernetes cluster is using a specific port to communicate with RabbitMQ cluster. On RabbitMQ I see that connection is coming from 192.168.1.10:34226. ...
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CENTOS 7 - Auto block IP with null routes
Whenever I notice overload on my media (videos) server, I check for ddos with this command from netstat:
netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
It shows currently ...
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1
answer
1k
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Remove tcp entry from netstat -a
I have a rather strange issue and no matter what I do or search, I cannot rectify it and have now decided to seek help here initially.
I have a cluster of servers, about 10 clustered together.
A few ...
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Why can't I ping 127.0.0.1 from some network interfaces?
I'm on OS Sierra.
This is (part of) what I get on ifconfig
...
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether 98:01:a7:b4:91:63
inet6 fe80::4e:52ae:9fa8:...
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1
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netstat vs nmap to find IPs in a local network
I'm in a local network : IPv4 shared address space (100.x.x.x). Connected to a wifi hotspot. Ip ranges : 100.76.164.0/23
When I run :
nmap 100.76.164.0/23 : It says all the hosts are down
netstat -...
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1
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netstat says connection in SYN_SENT but tcpdump captures no data
I'm debugging a ldap problem after ldap client machine upgraded to ubuntu 18.04. Trying to figure out where the problem is, and I noticed the outbound connection is in SYN_SENT, but when I use tcpdump ...
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Remote Client is unable to connect to TCP Server on VPS (Getting 10060 error)
I have searched all over the internet for the solution. Unfortunately, I could not get any working solution yet. Here is the story.
I am running TCP server for small communication application on the ...
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1
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netstat shows connected socket with path to it, but path doesn't exist
Im inside a docker container and ran netstat -x | grep docker
which got me the:
unix 3 [ ] STREAM CONNECTED 62288711 /var/run/docker.sock
unix 3 [ ] STREAM ...
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2
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how to get file download connections on linux
I have a site with video content (mp4 files).
When people are watching videos, they are downloading video files from my site. I want to know the number of the active connections via the linux ...
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On a web server, is it normal to see a thousand connections coming from one user?
When I saw so many connections from one IP (by using netstat), I thought it's bot.
(The website is not popular so it's very unlikely to be multiple users behind one IP.)
But I checked apache access ...
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0
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255
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Collectd won't open listener
So I've been stuck with this for sometime now. I want to use collectd with graphite. Im using centos 7. I've made the necessary changes in collectd.conf as seen below:
[root@relay-1 ~]# grep -v "#" /...
2
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1
answer
246
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why are there are so many svchost established connections to Isilon?
Our client has a Isilon (used only for smb) with few nodes attached to it. When I run TCPView I don't understand why svchost service established the connection and why there're so many of them:
And ...
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1
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347
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Uderstanding netstat output
When I run netstat -b on Windows 10
I get lots of results of similar nature
TCP 127.0.0.1:64248 LocalHostName:64249 ESTABLISHED
[w3wp.exe]
TCP 127.0.0.1:64249 LocalHostName:...
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1
answer
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Why is kjournald showing up 700 times in `netstat`?
AFAIK, kjournald is not a network program, but a program that deals with the journal of EXT3 (I am running EXT4 on Ubuntu 16.04). Still, when running sudo netstap -tapn it shows up almost 700 times, ...
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0
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How to configure Linux to close the connection if Send-Q is never sent?
There is a TCP client-server connection. The application on the server is sending data regularly. Client machine is then reset physically. Netstat shows Send-Q on the server is filling up, the ...
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