Questions tagged [netstat]
netstat is a tool for viewing active network connections, listeners and sockets.
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RHEL + how to know the limit of concurrent connections number per port?
how to know the number of concurrent connections per port on RHEL 7.x machines
for instance, let say we connect to port 9080 with XXXX concurrent connections.
wget http://server_mngmnt.jupiter.com:...
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Why "netstat" doesn't show the ip of a server I'm connected to?
I have an audio stream from a Youtube video obtained by youtube-dl -g <URL> (this command outputs two links, for video and audio respectively). They have this form; https://rr1---sn-uqx2-w50l....
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What does it mean when netstat outputs a dash in pid / program name column?
Here is some lightly modified output from netstat (I removed the addresses and names)
a@xxxxx:/app# netstat -p
Active Internet connections (w/o servers)
Proto Recv-Q Send-Q Local Address ...
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How to get the command of a process by an established port while ss, netstat and lsof failed?
Recently I have noticed extremely high network usage on a ubuntu server. I identified the port with nethogs. It connects to a SMB server within my LAN. It should be connected at boot for the dozens of ...
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Blocking traffic from specific countries. How to kill existing connection?
Using Linux Debian Bookworm.
Problem
I want to block all incoming connections to my server coming from specific countries.
Edit
As someone pointed out in the comments, I really shouldn't be doing this ...
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Difference Send-Q between netstat and ss
The ss send-Q column shows non-zero value constantly, while netstat shows Send-Q as zero for same port and same process. Can you please let me know why like this and what does mean by non-zero value.
...
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Martian packet with ARP broadcast traffic
Server nodes keep getting ARP broadcast traffic and becoming martian packets due to assymatric routing. I was known that when strict filtering is enabled with net.ipv4.conf.eth0.rp_filter = 1, the ...
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PHP Error waiting on socket
I'm getting problems with ssh2 and fread php function that started on a few days.
On the apache error log show:
ssh2_connect(): Error starting up SSH connection(-9): Error waiting on socket
fread(): ...
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netstat no support on this system [closed]
in dealing with try to resolve another issue into my Ubuntu 22 OS
I need to check out the ports that tightvnc is listening on for connections.
I use this command : sudo netstat -lvp | grep vnc
BUT ...
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What does "no ports" on netstat -s mean?
On Windows server 2016, when I execute, in a cmd prompt, "netstat -s" I get a bunch of statistics. One of those is "No Ports".
What does this mean? Is this the number of times ...
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Can't create a pseudo network interface on Debian 11
I have a KVM based Debian 11 (bullseye) VPS with internet access on eth0 network adapter. The public IP has been assigned by DHCP. The IPs and Routes are as what follows:
ifconfig and iptable BEFORE ...
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Take NetStat Dump After Every X Minutes
We have a lot of port exhaustion issues recently. I was reading https://learn.microsoft.com/en-us/troubleshoot/windows-client/networking/tcp-ip-port-exhaustion-troubleshooting?source=recommendations
@...
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NetStat Group By Process Id and Show Count
Is there any way to group the output given by netstat into process? I am running netstat -ano and doing manual count to know which process is using how many ports. I am using Windows Server.
We have ...
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What does `netstat -y` on Windows do?
From the help page of Windows netstat, I got this:
-y Displays the TCP connection template for all
connections.
Cannot be combined with the other options.
Google results are all same ...
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how to continues netstat a port and save it to text file with time stamp for each netstat
I am using a system which is integrated to other system using a specific port and recently I am facing multiple interruption in the integration, and I need to monitor the port "48823" for a ...
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How to tell whether a linux tcp socket had recent activity?
Most of the time, when changing or upgrading a network service, I would do this during maintenance hours but some services are rarely used so it is tempting to just check whether it is currently in ...
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Why NFS is listening to a port but not showing the process name, is there any security risk if no firewall is set?
I'm using ubuntu 22.04 and have mounted an NFS storage, here is my fstab file
ftpback-bhs5-26.ip-149-56-30.net:/export/ftpbackup/ns524316.ip-xxx-xxx-xxx.net /media/backup nfs vers=4.0 0 0
When ...
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How to identify which os process is establishing a proxy connection
Platform: Red-Hat 7
I hope you can help me with this. I've been told that one proxy server we are using is going to be decommissioned in the following days. I've tried to use netstat in order to ...
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Nginx change default IP form 0.0.0.0 to pecific IP
I have nginx running as a web server.
The virtual host have the IP specific configuration with IP addresses listed, however whtn I check netstat Nginx is litening on 0.0.0.0:80. I would like to change ...
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Early warning of port exhaustion in Linux
AFAIK, port exhaustion happens when a host is trying to establish a lot of connections to another server and the sessions used up all the available ephemeral ports. e.g.
192.168.1.1:port -> 10.20....
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How to block flooding "empty" connections from single IP
Right now netstat lists 200 - 4000 connections to the same IP in India. Seems like some kind of flooding attack to me.
e.g:
tcp 0 0 [removed] 182.65.238.[removed].in-:mysql TIME_WAIT
I've ...
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Show TCP keepalive status in Windows?
Using netstat -to on a Linux system shows the status of tcp keepalive for a socket like this:
Proto Recv-Q Send-Q Local Address Foreign Address State Timer
tcp6 0 0 ...
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How to find a malicious TCP program using netstat [closed]
I am trying to do a homework for a lab but have a quick question.
How do I find a malicious TCP service that is still running and the adversary has achieved persistence by creating a systemd service?
...
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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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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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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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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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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
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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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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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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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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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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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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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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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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 $5}' | grep -Eo '(...
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netstat how to exclude localhost from the result when using grep
When I run this command in my terminal:
netstat -an | egrep ":80|:443" | sort
I got this following output:
tcp 0 0 172.104.10.125:48310 172.104.10.125:8081 TIME_WAIT
tcp ...
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How can a server accept incoming traffic to port 443 if it isn't listed in netstat?
I have a server that is currently accepting HTTPS requests and the only thing that shows with netstat -plnt is this:
elijahlynn@web:~$ sudo netstat -plnt
Active Internet connections (only servers)
...
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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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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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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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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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211
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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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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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