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2
votes
1answer
29 views

Relationship between tcp state TIME_WAIT & HTTP keep-alive

What is the relationship between keep-alive on a HTTP request and a tcp socket in TIME_WAIT - should they be correlated? Furthermore, should system and web server settings be aligned e.g. ...
1
vote
0answers
63 views

How to force/fake linux eth0 in 'up' status even without cable connected?

One of my testing script is eth0 status related, when eth0 goes down(cable unplugged), the script exit, and i need to unplug and plug cable many times due to test needs. is there anyway can fake ...
0
votes
0answers
81 views

Tuning Apache KeepAlive Timeout for HTTPS

My website forces HTTPS everywhere and has an average first load time of 3-5 seconds. Thanks to caching, repeat load time is 0.8 seconds. The SSL negotiation takes 150-300ms on my server, so I want ...
5
votes
0answers
1k views

nginx connection timeout & client closed connection issue

I have this nginx server running on AWS & it was working all fine until recently when couple of users started complaining about the website not opening until they made some 10 attempts to access ...
1
vote
1answer
716 views

option http-server-close on HAProxy haproxy-1.5-dev19 will result in Connection: close header sent in response

I basically have the following issue: whenever I add option http-server-close to the haproxy config (either in frontend or backend section), haproxy will send a Connection: close header in the ...
0
votes
3answers
287 views

Which settings schould be changed to lower apache CPU usage and use more RAM?

On our CentOS 6 server, we have now a lot of CPU overload, while our RAM is almost not used. KeepAlive is set to "on" because we have some AJAX elements on your website and serving many files such as ...
1
vote
1answer
419 views

Apache: Force HTTP 1.1 or Persistent/KeepAlive connections for HTTP 1.0 requests

I want to force Keep Alive or Persistent connections for all HTTP requests on my Apache 2.2.3 server running on RHEL 5.8. A lot of web crawlers are using HTTP 1.0 for some reason, and I would like to ...
1
vote
0answers
44 views

tcpdump expression to show zero-byte ACKs?

I want to show zero-byte TCP keepalives sent and received. While this could be generally useful, in this particular case I want to prove that a change I made to the JDBC driver (adding ...
1
vote
1answer
2k views

Should `keepalive_timeout` be removed from Nginx config?

Which is the better configuration/optimization: to explicitly limit the keepalive_timeout or to allow Nginx to kill keepalive connections on its own? I have seen two conflicting recommendations ...
0
votes
2answers
143 views

Http Persistent Connection (keep-alive) and port numbers

Is a persistent http connection (keep-alive), always bound to a specific port, or can it use a range of ports?
0
votes
0answers
30 views

Are there security concerns involved with keepalive?

I'm configuring an IIS7 site for a third-party tool, and our team had a brief discussion about the keepalive setting. I have learned in my research that increasing this timeout will impact available ...
0
votes
1answer
99 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 ...
-1
votes
1answer
187 views

How do I change my ubuntu keepalive to infinity?

http://www.golinuxhub.com/2013/03/setting-up-custom-tcpip-keep-alive.html Once I connect to my development server, I don't want it to automatically disconnect unless I quit my terminal. What ...
0
votes
0answers
150 views

ORACLE keep-alives with ENABLE=BROKEN with ezconnect

Could you please advise is there any way to use ENABLE=BROKEN option with ezconnect? Usualy this option provided in tnsnames, but in case of ezconnect, tnsnames will not be used and option will not be ...
0
votes
0answers
121 views

Scriptable FTPS client able to send Keep Alive to control port?

We need a FTP client that satisfies the following constraints: Windows Command-line scriptable, so we can automate it...sorry, FileZilla (?) FTPS, as it seems to perform better than SFTP The ability ...
2
votes
2answers
911 views

Large keepalive_requests values are severely slowing-down Nginx

When running a bacon (43-byte transparent pixel) load test on Nginx, we have tried several keepalive_requests values (from 10 to 100,000) and the optimal value seems to be 10. Here are the server ...
1
vote
1answer
207 views

Do keepalives to socket connections exist?

Pre briefing: Although my question is broad on purpose, I am dealing with nginx connecting to php-fpm (fcgi), which is served via a local socket (/tmp/somesocket.socket). Nginx has a setting to ...
0
votes
1answer
165 views

Making Dovecot keep its TCP connections alive?

I'm trying to run a benchmarking application which connects to my IMAP server and has a "warm up" phase during which IMAP connections are being established. I've set my limits properly and the mail ...
3
votes
2answers
250 views

Trying to understand how keep-alive works

Today we encountered a problem on the server, when files/scripts took more that 3 seconds to load. The solution was simple - just increasing MaxClients to the estimated memory limit. But I am worried ...
0
votes
1answer
224 views

Is tcp_keepalive application dependant on Linux?

According to http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/index.html , the kernel keepalive function occurs at the OS level, and doesn't require an application to explicitly call it. However I also read ...
1
vote
1answer
522 views

HTTP Keep-Alive puzzle with EC2 Linux, Nginx and Chrome

Please, help to solve HTTP keep-alive problem. Basically, I have amazon-ami linux (v2012.09) on EC2 running nginx (v1.2.6). Chrome (v25.0.1364.99) accesses HTTP page normally, then after about 30 ...
0
votes
0answers
441 views

Incomplete page by nginx -> fcgi -> php-fpm with keepalive

I have problem somewhere between nginx and php-fpm. When I use keep-alive connection for fastgcgi php-fpm, there is often problem with loading page. Page not completely loaded. I tried to debug using ...
0
votes
2answers
513 views

In Nginx can I set Keep-Alive dynamically depending on ssl connection?

I would like to avoid having to repeat all the virtualhost server {} blocks in nginx just to have custom ssl settings that vary slightly from plain http requests. Most ssl directives can be placed ...
0
votes
2answers
238 views

Spawning HTTPD processes

Can any confirm how Apache spawns new children ? As in if I connect to a webserver (HTTP 1.0 / no keep alive) and issue a HTTP /GET I will be spawned a new HTTPD child. If then issue another HTTP ...
1
vote
1answer
191 views

Proxy to keep connection to API alive

On one server I have some 30 PHP sites running under Apache. All those sites use the same (HTTP) API to fetch some data. The API is hosted elsewhere (under my control) The API uses Nginx with ...
0
votes
1answer
2k views

NGINX : Keep alive requests to static content ok - Keep alive requests to php-fpm requests hang until keepalive_timeout is reached

FYI, the initial question I have posted is here, no need to read it as I was way off initially: NGINX + PHP-FPM - Strange issue when trying to display images via php-gd / readfile - Connection wont ...
0
votes
1answer
799 views

Nginx keepalive_requests - What value to use for unlimited?

We are using an nginx backend behind a nginx proxy. We use upstream keepalives. They work quite nicely. We were wondering, what value would we set keepalive_requests on the backend to set the ...
0
votes
2answers
886 views

mod_rewrite+proxy closes connections to backend (keepalive)

We have a fairly typical setup: client <-> apache2 (2.2.22) <-> backend (*). Initially we were using mod_rewrite with the [P] flag in the simplest form: <VirtualHost *:80> ...
2
votes
0answers
2k views

TCP Keepalive and firewall killing idle sessions

In a customer site, the network team added a firewall between the client and the server. This is causing idle connections to get disconnected after about 40 minutes of idle time. The network people ...
2
votes
1answer
502 views

Does apaches keep alive time-out reset every time a request is received?

The title of this question is pretty self explanatory, but: Does apaches keep alive timeout reset (as in, start again) every time a request is received? So for example, assume we have a 60 second ...
0
votes
5answers
2k views

keep ssh connection alive and persistant while switching network interface connections

Scenario: At my desk with laptop plugged in to ethernet and connected to remote server over SSH Want to move to other side of office with laptop and change to WiFi without interrupting SSH ...
2
votes
0answers
599 views

Is it possible to use local web.config to enable keep-alive?

Is there any way to enable keep-alive on IIS 7 in a hosted scenario? I attempted to use the answer to this SO question Where (or how) is the keep-alive setting in web.config?. I added the following ...
5
votes
7answers
3k views

How can I avoid heroku stopping my dyno?

I build MVP's for clients regularly. Often I deploy on Heroku so they can see if the product works and demo it to prospects and investors. Then I have an application deployed on heroku, and it works ...
0
votes
2answers
642 views

keepAlive in Apache causing apache to reach its max_clients

I have an Apache 2.2 running on ubuntu 11.4 with 16Gb RAM, for image hosting from mobile phones through GPRS,since connection is slow i have enabled keepalive and set time out to 6,**based on average ...
1
vote
1answer
563 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 ...
0
votes
1answer
208 views

Keep alive and Max_client issue in Apache

I have installed Apache/2.2.17 on ubuntu 11.4(64bit) ,with 48 GB of RAM, and set KeepAlive ON MaxKeepAliveRequests 100 keepalivetimeout to 6 (since lot of dynamic images) StartServers 100 ...
1
vote
1answer
2k views

Is it better to disable Keep-Alive in IIS 7 for high traffic web applications?

The advice below applies to Apache, but it seems generic enough to apply regardless of system. My architecture is 3 web servers behind a load balancer. My IIS servers currently have keep-alive enabled ...
0
votes
1answer
456 views

Keep-alives are not working for websites with NodeBalancer in Linode

I have following configuration in my linode slice NB <----->web1+web2+web3 Here's the configuration screenshot from linode: We need NB in http mode since we need few things that plain tcp mode ...
6
votes
2answers
6k views

What is the difference between keepalive and heartbeat?

I want to structure a high available server cluster . Now I want to know detail about keepalive and heartbeat, what is the difference between both, and How to choice one.
2
votes
0answers
263 views

A tool to measure overhead of establishing TCP connections

I need a tool which would while doing port forwarding measure how much time was spent establishing TCP connections vs total time passed. Charles debugging proxy has the port forwarding feature and ...
1
vote
2answers
417 views

Is It Better to set KeepAlive to 1 second rather than turning it off all together?

I've heard setting keepalive timeout at too high a number will diminish its value. So, to be on the safe side, and still somewhat benefit from it, can I set it to 1 second ? Or will setting it to 1 ...
0
votes
2answers
100 views

Keeping connections open

I'm new to cURL and I'm trying to do something reasonably simple. I want to login to a server and download data at regular intervals over a few hours. First, I login to the server - which I've ...
1
vote
3answers
76 views

Can I get a router to call a url on a timer?

I am responsible for a small network spread over several buildings. We have accommodation areas that have a router providing access to the internet to guests. I would love to be able to get the ...
0
votes
1answer
5k views

How to find the connection time-out value in linux?

I am setting up a nginx webserver with php-fpm and (d)dos deflate to ban attacks. Now currently there is no traffic to my server at all, as i'm testing things. With this command i can see who is ...
2
votes
1answer
689 views

Keeping a Python Script alive after leaving SSH Client?

I have a while loop in my Python Script and its independent script so I can't run it as a daemon. Also I have tryed using nohup, but I'm having this error: root@ubuntu:~/Desktop/starthere-group-ok# ...
1
vote
1answer
4k views

Keep-alive options not working on Linux for an outgoing connection

Does anyone know if Linux supports keep-alive socket options on an outgoing connection? I made an outgoing connection with keep-alive options but netstat --timers shows off (I'm assuming timers are ...
6
votes
1answer
10k views

How to adjust nginx keepalive_timeout?

I am using nginx along with php-fpm to server a busy mysql-based site. Currently I am using keepalive_timeout = 5, however I have no clear idea about how to optimally adjust it. So appreciate your ...
6
votes
2answers
3k views

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 ...
4
votes
2answers
3k views

keep-alive or not keep-alive

My company is launching a new website with potentially large waves of visitors in very short windows (estimate is around 14k visitors in a 2 minutes window). So, I'm reviewing our configuration, and ...
3
votes
2answers
3k views

How to test keep-alive is working on client end

What are some different ways/tools to verify that keep-alive is working on the server from the client's end?