Questions tagged [connection]
A connection generally refers to a TCP/IP connection, that is established as the result of the handshake between 2 hosts.
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Why do consoles sometimes hang forever when SSH connection breaks?
I've seen this with so many consoles (on Linux, Mac, ...), and with lots of different machines in many different networks. I can never pinpoint the exact reason, why this happens: All you have to do ...
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ssh tunnel refusing connections with "channel 2: open failed"
All of a sudden (read: without changing any parameters) my netbsd virtualmachine started acting oddly. The symptoms concern ssh tunneling.
From my laptop I launch:
$ ssh -L 7000:localhost:7000 user@...
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What causes SSH error: kex_exchange_identification: Connection closed by remote host?
I setup a SSH server online that is publicly accessible by anyone. Therefore, I get a lot of connections from IPs all over the world. Weirdly, none actually try to authenticate to open a session.
I ...
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How to force MySQL to connect by TCP instead of a Unix socket?
I would like to analyze mysql traffic. Right now, all mysql requests are sent to the MySQL unix socket:
unix 2 [ ACC ] STREAM LISTENING 3734388 15304/mysqld /var/run/mysqld/...
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I accidentaly forbid SSH connection to a remote server... What's next?
Let's say it again, we all make mistakes, and I have just made one.
A brief history: I was doing some stuff on a VPS (Debian) I'm renting, when I noticed some strange behaviour. Using the netstat ...
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Optimal value for Nginx worker_connections
Nginx worker_connections "sets the maximum number of simultaneous connections that can be opened by a worker process. This number includes all connections (e.g. connections with proxied servers, among ...
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How do I allow outgoing connections via iptables?
I have two servers. The program on the first needs to communicate with the second on port 2194.
I know its not working, because when I do:
root@server1 [~]# telnet myserver2.com 2194
Trying 123.123....
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SQL - an error occurred during the pre-login handshake
Until yesterday evening, I was able to connect to my server from my local machine. Now, I get the following error:
A connection was successfully established with the server, but then an error ...
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5
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Understanding this error: apr_socket_recv: Connection reset by peer (104)
So, if I do some benchmarking with apache benchmark (ab), and I use large numbers of requests. Then sometimes in the middle of a test I get this error.
I don't even know what it means. So how can I ...
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Finding short-lived TCP connections owner process
Running tcpdump on local connections to an apache server, I found TCP connections being established and closed immediately every 2 seconds. How do I find which process is responsible for these? ...
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Why are connections in FIN_WAIT2 state not closed by the Linux kernel?
I have an issue in a long-lived process called kube-proxy being part of Kubernetes.
The problem is that from time to time a connection is left in FIN_WAIT2 state.
$ sudo netstat -tpn | grep ...
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RDP fakeout when connectiong: does nothing, no error
Using windows RDP, I'm trying to connect to a remote machine to which I connected fine moments earlier. I had to reboot the server...
Now, I type in my credentials and it looks like its working (the ...
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Siege: descriptor table full sock.c:119: Too many open files
I am trying to make a stress test in my own server using siege with the following command:
$ siege -c 500 myweb.com/somefile.php
But I get this error:
[error] descriptor table full sock.c:119: Too ...
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wget ftp connection failing after PASV command
In attempting to transfer all files from one web server ("source") to another ("destination"), the wget command is connecting via FTP, but cannnot proceed beyond the PASV command.
I'm using an SSH ...
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apache webserver unresponsive with server-status showing all child processes waiting for connection [closed]
My setup:
I have 3 nearly identical webserver machines serving the same high loaded dynamic website with simple load balancing over dns. The service has been working for over two years with the same ...
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Remote connection to MySQL server takes very long
I have a MySQL 5.0.75 server running on my Linux notebook to which I want to connect from another machine in the local network.
This connection takes 5-6 seconds:
mysql -h 172.22.65.101 -u myuser -...
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2
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Impact of Connection Close vs Keep-alive
I'm configuring our servers, and due to the nature of our load balancer, we can't send connection keep-alive headers. I'm trying to determine the impact of sending these headers to both the end-user ...
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tcptrack shows SYN_SENT connections, does that mean the SYN package reached the server?
our server suffered a serious connection timeout problem, so we track tcp connection with tcptrack
we found out that, if the client started to connect to the server, tcptrack shows the connection, ...
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3
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Log connections to program
Besides for using iptables to log incoming connections..
Is there a way to log established inbound connections to a service that you don't have the source to (suppose the service doesn't log stuff ...
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Connection error to mysql database
My application needs to do quite frequent connects to a mysql database on another machine. However I get frequent errors on connection; I can usually eventually connect but after many retries. The ...
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PHP/mySQL: how to debug a 'too many connections' error?
I am working right now with PHP website on my client's dedicated server and I get periodically an error too many connections but ~5 users are browsing this page.
In phpMyAdmin I can see that max ...
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Cannot connect to Redis installed on VirtualBox running Ubuntu from Windows 7
I've setup an Ubuntu image on VirtualBox on a Windows 7 host. On the Ubuntu guest I've installed Redis which runs on port 6379 (TCP) by default.
I've setup port forwarding using the VirtualBox GUI ...
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What does ConnectTimeout in ssh_config mean?
Local and remote os are all Debian8.
I want to keep ssh alive for a long time.
The configuration file /etc/ssh/ssh_config on my client(local) side.
Host *
ServerAliveInterval 60
...
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Can I make TCP/IP session to run less than 60 seconds?
Our server is overloaded with TCP/IP sessions, we have 1200 - 1500 of them.
Most of them are hanging in TIME_OUT state.
It turns out that a connection in TIME_OUT state occupies a socket until 60 ...
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4
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Able to connect by SSH, but not x2go [closed]
I am having trouble connecting to a remote server with X2GO using a DSA key. Connecting works fine over SSH, but when I try to connect with X2GO, it goes immediately to the username/password box and ...
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What is the proper HTTP status for "too many connections?"
I am working on an HTTP server which is supposed to only allow a certain amount of connections per user. How do I gracefully tell the user that more than n connections are not permitted. I tried ...
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Certificates in SQL Server 2008
I need to implement SSL for transmissions between my application and Sql Server 2008.
I am using Windows 7, Sql Server 2008, Sql Server Management Studio, and my application is written in c#.
I was ...
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https lingering TIME_WAIT connections
From my client PC I'm connecting to a webserver, it uses HTTPS only.
When I connect I see in TCPView (sysinternals tool alternative to netstat) a lot of TIME_WAIT connections to the https endpoint.
...
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Load balancing MySQL using HAProxy: Got an error reading communication packets?
I've set up load balancing MySQL slaves using HAProxy via a xinetd. 2 load balancers shared a virtual IP that is managed by Pacemaker:
crm configure show:
node SVR120-27148.localdomain
node SVR255-...
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How can I find the total number of TCP connections for a given port and period of time by IP?
On a Linux system there are plenty of methods for listing the current TCP connections for a given port by connecting IP but: how can I count the total number of connections to a port per source IP for ...
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When using nmcli, what is considered a device, an interface and a connection? What's the difference? [closed]
What are dependencies and relations between device, interface and connection in nmcli cmdline utility under linux?
The below questions are asked in context of nmcli and networking in linux:
Which ...
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Why would a client send a RST packet as reply to a SYN,ACK?
I have a HTTP webservice where sometimes the connection setup fails in a strange way:
client sends a SYN packet
server sends a SYN,ACK reply
client responds with RST
In which situations could a ...
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Can't connect to MySql server on remote server
Connecting to: CentOS v?? with MySql 4.?? in Nashville (example public ip=11.11.11.11)
Stack: Cable modem as gateway > router with forwarding > CentOs Box
Connecting from: Windows 2003 R2 in ...
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random CONNECTION_RESET on apache2.4 debian 9
My server has some strange behaviour and I just cant find the cause. I've been looking everywhere.
I will pay 200$ worth of bitcoin to anyone who can figure this out.
The problem:
When requesting ...
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Redis connection issue
We are currently experiencing a lot of Redis errors with the message
Unable to connect: read error on connection, trying next server
We run Redis on FreeBSD using PHP Redis and we have a hard time ...
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Is it possible to see active connections in nginx?
Is it possible to see what URLs are actively being served by nginx (i.e., see the URLs that are in the middle of being responded to, not the ones that nginx has finished responding to).
I would like ...
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PPTP connection fails with errors 800/806
I've got a client (Server 2008 R2) that won't connect to our production environment PPTP VPN server (Server 2003, running RRAS).
The server is behind a firewall that has TCP1723 open as well as GRE. ...
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Network packet size on sql server connection string to improve throughput
We have a dataload job that moves a relatively large amount of data across the network between two sql servers. the servers are on the same subnet and there is only a switch between them. the data ...
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nginx connection reset
When first visiting my site after not visiting it for a few minutes, the connection is "reset" 100% of the time.
I get this message when debug is turned on, along with a 400 bad request status ...
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mysql connection is slow (5seconds)
After building my webapp on a first boot i create 2 connections to mysql on debian then 1-2 (r/w) for every page after that. The connection consistently take 5.2 seconds to connect. Debian is in a VM ...
user274
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Effects of internet connection speeds on server queries
Can my internet connection significantly effect queries run on phpmyadmin? I am currently 18 down and 30 up. I switched internet connections today and noticed a deep drop in query performance.
The ...
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How to wire 20 computers and 20 phones and 1 server into LAN?
I have currently 3 switches
Two Netgear JFS524 with 24 slots,
One Belkin with 16 slots.
Server
DSL Internet Router.
Main question is how to connect switches together, two Netgear's are next to each ...
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What is the typical maximum number of database connections for Oracle running on Windows server?
We are maintaining a database server that serve a large number of clients. Each client typically running several client-applications. The total number of connections to the database server (Oracle 9i) ...
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Fast, reliable data transfers from/to China
We are a small company and we will need to transfer rather large amounts of data (10GB+ each time) between Europe and China in the near future.
As many may have experienced, Internet connections to ...
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Odd TCP termination sequence
While troubleshooting another thing, I've noticed an odd pattern of TCP closes.
Packets: http://www.cloudshark.org/captures/7590ec4e6bef
What's happening is that the last few packets of the close ...
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Should the database connection limit equal the number of processes connecting?
I noticed that PostgreSQL and MySQL have a 100 client connection limit by default. I'm wondering if I should turn this down since the webserver is on the same box and I only have about 20 PHP ...
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IPtables rate-limit, What are the differences between modules? Recent, Limit
I am doing some rate-limiting with IPtables, and i'm not sure if I should use "Recent" or "Limit"
What are the differences between the two? If they both achieve the same result, which one has ...
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Connecting to AS/400 hardware
In about 2-3 weeks I'm getting an old AS/400 server (something 9406, probably 6xx or 8xx) to learn OS/400 from administrators point of view.
Will I need some special hardware to connect and do IPL (...
feshi
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connection sync suggestions with HAproxy and keepalived
I managed to get HAproxy working in a failover configuration as suggested on the architecture.txt document using keepalived.
I used CentOS 5.5, HAproxy rpm (haproxy-1.3.25-1.el5) from epel repo, and ...
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Internet Forwarding With Qemu?
I'm using kvm and qemu to run a windows virtual machine, but I'm trying to get internet on that machine. I've been reading about all this bridging and stuff that is done to do that, but I was ...
ConfusedGuy