Questions tagged [keepalive]
The keepalive tag has no usage guidance.
122
questions
4
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answer
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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 ...
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23
votes
3
answers
54k
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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 ...
- 331
3
votes
1
answer
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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 ...
- 163
0
votes
3
answers
3k
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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 ...
- 167
5
votes
2
answers
4k
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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 ...
- 606
1
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0
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620
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 tcpKeepAlive=...
- 1,105
15
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1
answer
34k
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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 ...
- 263
0
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2
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4k
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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?
- 367
1
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1
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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 ...
- 203
1
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1
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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 ...
- 8,591
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748
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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 ...
- 274
4
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2
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6k
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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 ...
- 307
1
vote
1
answer
2k
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 ...
- 1,078
0
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1
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1k
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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 ...
- 203
4
votes
2
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3k
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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 ...
- 305
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1
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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 ...
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1
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3k
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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 ...
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1
vote
2
answers
6k
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 ...
- 469
1
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2
answers
2k
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 /...
- 155
3
votes
3
answers
4k
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 keep-...
- 31
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1
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8k
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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:
https://serverfault.com/questions/427296/nginx-php-fpm-strange-issue-when-trying-to-display-images-via-...
- 1,078
4
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1
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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 ...
- 1,078
3
votes
3
answers
5k
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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>
...
- 145
11
votes
1
answer
35k
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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 ...
- 211
2
votes
1
answer
2k
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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 ...
- 1,078
22
votes
11
answers
25k
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 ...
- 383
1
vote
1
answer
3k
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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 ...
- 123
6
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7
answers
9k
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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 ...
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0
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2
answers
3k
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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 ...
- 1,520
1
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1
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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
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1
answer
443
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
...
- 1,520
1
vote
1
answer
6k
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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 ...
- 426
0
votes
2
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944
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 ...
- 2,548
21
votes
2
answers
33k
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.
- 997
2
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0
answers
597
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 ...
- 267
3
votes
2
answers
2k
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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
2
answers
588
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 ...
- 3
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vote
3
answers
123
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 ...
- 767
2
votes
1
answer
36k
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 ...
- 1,481
2
votes
1
answer
2k
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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# ...
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8
votes
2
answers
21k
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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 ...
- 131
13
votes
1
answer
51k
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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 ...
- 3,157
9
votes
2
answers
22k
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 ...
- 117
7
votes
2
answers
8k
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 ...
- 3,017
24
votes
2
answers
48k
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?
- 393
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1
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809
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Apache Timeout/KeepAlive
I run several apache web servers on CentOS 5.x and they all seem to have the same problem. It is typically fast but at times the browser will just sit there waiting forever and it never fails or goes ...
2
votes
1
answer
1k
views
HP switch 'mirror port' makes a Cisco switch port err-disabled due to keepalive loop-back
I'm trying to connect an HP ProCurve 5304xl switch to a Cisco 2950. The HP port I'm connecting to is described as a 'mirror port', which appears to be like a SPAN port except that it also allows ...
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votes
1
answer
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Keep-Alive and Timeout Behaviours between different browsers on Windows
Short Version
Why does chrome send out keep-alive's while IE and FF don't?
Long Version
Initially, I thought this was a server-side issue.
I've got an apache server that's a frontend proxy for a ...
- 255
0
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1
answer
3k
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Is this normal? Multiple httpd process
I'm testing a new Server. This isnt really a peak time for my server (2pm), but still its running a bit slow, I was checking the ESTABLISHED connections using the following command:
# netstat -ntu | ...
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1
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how do i turn on the Keep Alive and HTTP Compression in Apache server 2.2( centos)
how do I turn on the
KeepAlive and HTTP Compression
in Apache server 2.2(centos)
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