5
votes
6answers
354 views

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 ...
5
votes
1answer
67 views

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 ...
0
votes
0answers
81 views

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 ...
-1
votes
1answer
49 views

How do I know that my TCP connection is safe from the Firewalls/NAT?

Being on the Azure cloud, I found that the firewalls there drop connections between the Web server and the database quite often. Mostly when there was some inactivity, I think something between 5 and ...
0
votes
2answers
56 views

MySQL connection errors when client server bandwidth is exhausted

I have several servers with a lot of outgoing traffic using nginx. When the bandwidth is exhausted (1Gbit), I have problems connecting to my mysql server from those servers. The connect always fails ...
0
votes
1answer
34 views

What packet to ignore to not have ssh terminated on brief connectivity loss?

It seems like sometimes there are some connectivity problems around the edge of our network to certain other networks, and my ssh sessions with some remote servers, which themselves have no ...
0
votes
0answers
38 views

Apache process 100% with IPV4 TCP 10u

Today i got strange http ussage. All apache processes woks ok but after some time i found few processes stocked at 100% and they are like that long time. After i checked that process id at webmin ...
3
votes
0answers
210 views

Unix socket connection limit

This may appear like an already discussed/answered question. But I am specifically looking for info which I couldn't find anywhere answered clearly. I have an Nginx + php-fpm setup which uses unix ...
0
votes
1answer
706 views

Newbie, need help deciphering firewall log files (Cisco ASA 5520)

I'm not very familiar with firewall log files, or many of the terms involved in server connections. The lines in question involve a foreign, unauthorized IP interacting with a firewall (Cisco ASA ...
0
votes
1answer
139 views

Can't connect to my own machine through public IP

I couldn't figure out why I can't make a connection through my public IP. When using a local IP it works. I have the proper firewall port exceptions, and my router NAT has the configurations for port ...
1
vote
2answers
176 views

TCP vs UDP Error-Checking

I've bounced upon two articles that describe in-depth on how TCP and UDP connections work. However there is some kind of inconsistency. Where one article tells me that UDP does no Error-Checking at ...
3
votes
1answer
112 views

TCP 443 Connection goes into server but never reaches Apache2 (Passenger)

We have some weird problems, when external servers try to connect to our Website on Port 443(TCP) which is an Apache2+Passenger and a Rails Application. The problem only happens rarely. I started to ...
3
votes
1answer
817 views

Windows server closes TCP connection immediately after sending SYN+ACK

After a proper SYN, SYN+ACK and ACK TCP-Handshake, the server immediately sends a FIN+ACK indicating a graceful connection closure. The client's HTTP requests results in RST packets from server. This ...
2
votes
0answers
96 views

what can put linux process managing connection pool into bad state, so it restarts them continously?

I have an application with pool of connections to MySQL. At some point, in production, every 1-3 seconds some socket is closed. As a result my app restarts this connection. This is pretty big pool ...
1
vote
2answers
3k views

Increasing of max (more than 10) TCP Connections

I have the following problem on one of my servers: On other servers max TCP Connections is dynamical and much more higher than 10. How to increase max TCP Connections in this server in Windows ...
-3
votes
2answers
54 views

You are given a Computer, which is “somehow connected to the web”. How do you find out how? [closed]

The way to accomplish this obviously depends on the operating system. Windows 7 Mac OS X Mountain Lion Ubuntu 12.4 Choose one of the above (preferably all 3), and explain how: You would find out ...
1
vote
2answers
2k views

TCP connection stuck in SYN_RECV state despite ACK received, Linux 2.6.18, embedded, ARM

My client cannot connect to my protocol port (TCP) after some network glitches, even though all other protocols (telnet/HTTP/FTP) work fine. netstat shows that my server is listening and tcpdump on ...
0
votes
0answers
952 views

Connecting To FMS Server Issues

I am trying to get my computer to connect to an Adobe Connect server but I have had no luck. The error that Adobe is telling me is "ERROR: FMS Server did not return correctly!" and have done some ...
1
vote
1answer
3k views

TCP connection reset in linux(strange packet loss) but not on windows

It is all good on windows, but on linux when I try to retrieve a specific web page, I get a long wait and then a "connection reset by peer" Pinging destination IP works fine. I tried to reduce ...
3
votes
1answer
823 views

Unclosed TCP connections in CLOSE_WAIT for various processes

I have cluster of several machines connected on 10GBE network (NICs are Intel 82599EB 10GBE SFI/SFP+) running under Debian 6.0 and faced with problem of hung up TCP connections in CLOSE_WAIT state. I ...
1
vote
1answer
456 views

netstat reports ESTABLISHED connection even after I've pulled the cord

I'm experimenting with lost connections between my java application and my mysql server. The application and the server are on two different machines and I'm pulling the physical cord between the ...
1
vote
2answers
407 views

Clients can make maximum only 15 connections to ubuntu custom server

I have a custom server in C# being run on Ubuntu 9 under mono. I can make up to 15 silverlight clients connect to the server. When I make the 16th, it just waits. And if I close one of the established ...
0
votes
2answers
276 views

TCP what's the purpose of the third step of 3-way-handshake [duplicate]

Possible Duplicate: Why is it 3-way-handshake and not more? Example: If a client wants to talk to a server, it just tells the server that it wants to establish a connection, then the server ...
0
votes
1answer
123 views

Is a retransmitted SYN *EXACTLY* the same as the original?

If I have a client trying to connect to a TCP server, and the client sends a couple of retransmits trying to establish a connection, is there ANY difference in the SYNs it will send? If the server ...
5
votes
1answer
2k views

apache webserver unresponsible with server-status showing all child processes waiting for connection

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 ears with the same ...
2
votes
1answer
883 views

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? ...
4
votes
6answers
558 views

Effect of distance from server on page load speed

I measured the load speed of a static image file severed by nginx from my server (using pingdom service). The server should normally process this request within few seconds. My server is located in ...
0
votes
2answers
340 views

SSH occasionally (rarely) doesn't connect

I've been running this script for a few days: while [ true ]; do ssh USER@SERVER echo -n . || date +"%s"; done Obviously, my terminal is filled with dots, but sometimes (quite rarely) I get this ...
0
votes
1answer
899 views

What is responsible for Connect/Send/Wait in a HTTP request?

Services like pingdom and Google speed analyze the time consumed for reading a HTTP file. This includes DNS: Obviously, DNS management to interpret the namespaces is responsible. Connect: ??? Send: ...
4
votes
1answer
853 views

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 ...
1
vote
2answers
5k views

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, ...
0
votes
1answer
291 views

Windows Server 2008 not accepting connections to Server Programs

A company which our agency works for got a Windows Server 2008. I've had the job to install an FTP-Server (FileZilla Server) on this Windows Server 2008. Now my problem is that the server does not ...
0
votes
4answers
5k views

Windows Server 2008 R2/IIS 7 refuses all outside tcp connections

I am unable to connect, for example, via http to a brand new installation of 64-bit Windows Server 2008. The server is on a domain, but is not DC (that's another problem altogether). The IIS7 is ...
-3
votes
1answer
334 views

tcp connection refused

I am getting following error when running a program 2011/07/06 18:21:08 stat http error: dial tcp localhost:3179: dial tcp 127.0.0.1:3179: connection refused 2011/07/06 18:21:08 Error putting file: ...
2
votes
1answer
211 views

Is there any restriction of new incoming/outgoing TCP connections/seconds in Windows?

Is there any restriction of number of new incoming/outgoing TCP connections/seconds in Windows? If so, are there any differences between Windows versions?
3
votes
1answer
97 views

Can a TIME_WAIT connection be restored?

Is it possible to restore a connection that is in state TIME_WAIT? If not, I use raw packets (forgering the source), is it possible? (Please understand that I do not intend to do bad things, it's ...
2
votes
1answer
329 views

How to route all outgoing TCP connections using HTTP CONNECT on Linux

I have a Linux system which is behind a firewall, but it can connect to a HTTP proxy which passes all CONNECT commands through. How can I configure the Linux system to make DNS requests over TCP over ...
0
votes
1answer
1k views

Windows TcpNumConnections registry key

I hope this question isn't out of place here, but can anyone explain to me what the 'TcpNumConnections' registry key does? The description has me confused; I'm not sure what Microsoft means by ...
8
votes
3answers
1k views

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 ...
4
votes
6answers
694 views

What causes a delay of 100 ms in initiating an HTTP connection?

Settings: this is a quad CPU machine, plenty strong, not loaded at all (neither CPU nor network), the client is a Windows Server 2008 64bit, the server is a linux box. I have four threads that are ...
2
votes
1answer
1k views

Apache Timeout directive not working?

I have configured /etc/apache2/apache2.conf with Timeout 5 instead of the default 300. So I understand it should close an incoming connection after 5 seconds of inactivity. But I make a telnet ...
0
votes
2answers
2k views

Windows Server 2008, Stuck on TCP Handshake

The problem: My Windows 2008 Server cannot establish TCP connections with remote machines. Steps to reproduce: I have a service running on a Windows 2008 Server machine on port 40.000 with the ip ...