Questions tagged [keepalive]
The keepalive tag has no usage guidance.
122
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Enable keepalive or connection reuse in forward proxy
I need to setup a forward proxy in this way:
application server ---> forward proxy ---> internet (every site from internet)
For example: curl --proxy http:my-proxy.com:8080 https://google.com
It ...
- 113
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34
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Tracing / Solving a sudden spike in Apache2
My server is running on Ubuntu20.04, a pure LAMP stack with Apache 2.4.41.
In the last few weeks, there was a total of 2 occurrence where Apache2 was not responsive (users can't load our website), and ...
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1
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What's the difference between Nginx 'keepalive_time' and 'keepalive_timeout'?
In official Nginx docs a new directive added since v1.19.10 named keepalive_time 1h:
Nginx keepalive_time Doc
Limits the maximum time during which requests can be processed through one keep-alive ...
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532
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NGINX proxy_pass Keep-Alive without upstream directives
I have an nginx configured to dynamically proxy to another network, say ourdomain.com/legacy/otherdomain/443/examplepath?examplearg=examplevalue will be mapped to otherdomain.legacydomain.com:443/...
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2
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apache2 server keepalivetimeout is getting ignored and client always gets close_notify at consistent time
My client requires the server connection to be persistent for long durations to support old software. I have tried changing the Apache2 KeepAliveTimeout to 0, 5, 30, 100 for testing, but the ...
3
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1
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1k
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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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472
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configure inactivity timeout while handling keepalive probes
I am developing a TCP echo server using python and the socket library.
I'd like to have a timeout configured for each incoming connection. So to drop and close them if there is inactivity for a ...
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252
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keepalived virtual and real server in different subnets
My goal is to forward the SMTP traffic from one unused server to another using keepalived.
The problem is, that the other SMTP server is in different subnet. I have configured keepalive in the ...
- 111
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3
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9k
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Risks of enabling nginx upstream keepalive
Using nginx as HTTP reverse proxy for Apache with PHP backend (I need .htaccess flexibility for webmasters).
Seeing http/1.0 used in Apache logs made me look up on how to enable keep-alive connection.
...
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993
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Nginx upstream server - client broken connection not timeouting
I have a long poll clients that connect to nginx and upstream to kestrel dot net.
Clients have keepalive set that after 2 minutes connection breaks. On nginx side i have listen 0.0.0.0:xxx ssl ...
- 115
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2k
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keepalived - "notifiy_master"/ "notify_backup" does not start/stop application
I want to start/stop a freeradius depending on the master (start) or the backup (stop) state of the keepalived instance. The freeradius is listening for accounting messages on the shared virtual ip.
I ...
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1
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912
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nginx detecting dead clients
Normally when you pull the network cable out of a network device (which simulates some drop on the network, so an obscure disconnect), the underlaying sockets do not detect a disconnect (at least our ...
- 115
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1k
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Keepalived VIP not getting updated MAC after failover
I've got keepalived set up on 2 RHEL7.8 VMs to provide HA for a shared VIP. The VIP works and properly switches to each server when expected. I experience two issues related to the MAC not getting ...
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487
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Apache - Loading is very slow after inactivity. Most states of connections are in K - KeepAlive
I enabled the apache status module, and saw that most of the connections on the apache scoreboard are showing a "K" value.
On my server, when I enable KeepAlive, during inactivity it takes a ...
2
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1
answer
2k
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Nginx upstream keepalive with SNI
I've got Nginx setup to proxy two subdomains. SNI is used so each subdomain has a different SSL certificate. Nginx setup is roughly:
upstream a_example_443 {
server 1.2.3.4:443;
keepalive 128;
...
- 204
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2k
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How to tweak nginx keep-alive settings when you can't guarantee routing to the same host?
I have a scenario where a number of servers are running an nginx instance. For what it's worth, these are mostly just proxied requests. These hosts all sit behind a hardware load balancer and it's not ...
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Why nginx keepalive_timeout doesn't work?
I have the nginx-server and I need big keepalive_timeout for my api.
In nginx.conf I write
keepalive_timeout 300;
And run apache benchmark test
ab -kc 100 -t 30 http://172.16.31.03/
But after ...
- 65
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772
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How to determine if I should use KeepAlive in apache?
I have read several posts and questions about KeepAlive but have not found any suitable for me.
I have a server with just one client (Trivago) doing hundreds of (hotel availability) requests per ...
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4
answers
19k
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How to disable keepalive in curl
I'm trying to figure out how to consistently turn off keepalive across various client machines which are issuing HTTP requests via curl.
This is my target server:
- Ubuntu 18.04.2 LTS
- 4.15.0-47-...
- 804
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3k
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keepalived not promoting BACKUP to MASTER in multi-instance configuration
I'm trying to make a multi-instance keepalived to control a master-replica pair of tarantool servers and setup VIPs. Server state itself is managed outside keepalived. Keepalived should only manage ...
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2
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352
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TCP KeepAlives with NAT?
We have a Network set up like this:
MQTT Client -- TCP Forward (Netscaler) -- TLS Termination + TCP Forwarding (HAProxy) -- MQTT Server
For several reasons we needed to turn on TCP KeepAlives in ...
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1
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5k
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AWS API Gateway with Lambda and KeepAlive (persistent connections)
I'm a bit confused about Keep-Alive with AWS API Gateway.
Is this something I need to configure? or maybe be careful with this setting?
Because I will use API Gateway to execute Lambda functions, and ...
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Difference between keepalive in apache2.conf and in ProxyPass
I am using Apache 2.2.22
What is the difference, if there is any, between the Keepalive directive in /etc/apache2/apache2.conf
#
# KeepAlive: Whether or not to allow persistent connections (more ...
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1
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2k
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git push fails - permissions and ssh keep alive checked - what else?
I migrated my git server to a new server and now I try to push my data to the new one.
Client: Windows, TortoiseGit
Server: docker git-server
The log when trying to push
git.exe push --progress "...
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1
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2
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2k
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Can TCP Keepalive technique be used to prevent DDOS?
I am learning about DDOS and the techniques to mitigate it. TCP Keepalive is used to check if the other host is still up and if the host does not acknowledge the tcp keep alive message, the connection ...
- 131
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2k
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Apache2,4 + Prefork + Keep-alive On
I'm trying to speed up a website with a lot of images that are served from a separate subdomain static.example.com (same IP as www.)
Using the pingdom tool noticed that first 5-6 requests (on static....
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2
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4k
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how to emulate a browser that doesn't have "Keep alive"
I have a remote webserver listening on port 80, which serves a page which loads 100 individual .png files (from the same server and hostname) via 100 <img /> tags. On that remote server I do ...
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2k
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Amazon ELB doesn't clean up KeepAlive connections
AWS documentation mentions the following:
To ensure that the load balancer is responsible for closing the
connections to your instance, make sure that the value you set for the
HTTP keep-alive ...
- 111
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758
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How to make nginx mail auth connection persistent?
We are using nginx 1.7.3 as a reverse proxy for our Mail SMTP service. For authentication of each SMTP connection, we have configured nginx to connect with a http based service for authentication. ...
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1
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412
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Apache on Windows occupied by Chrome keep-alive
Chromes keep-alive packets seem to block Apache from answering all requests from other clients. They do not appear in the access log nor in mod_status and the browsers keep waiting for an answer. This ...
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173
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Apache delays serving an empty html file while processing a concurrent request
I have a website, which queries a Varnish server, which queries an Apache server, which queries a db server.
At 07:00:00, a request is send to the Apache server, which triggers a db request that ...
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4k
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jenkins cli build via ssh is disconecting after 10 minutes
I have two jenkins instances. I want job at 1st instance to invoke job at 2nd instance, wait until it ends and perform some actions (using artifacts produced by job @ 2nd)
I've come up with this ...
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1
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Why can't Nginx reuse connection to upstream while serving sequential requests from clients?
As mentioned in http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive
It should be particularly noted that the keepalive directive does not limit the total number of connections to ...
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906
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Unable to get Nginx/Apache + FastCGI + PHP-FPM + HTTP/1.0 to use Keep-Alive
For a reason beyond my control (an app that cannot be modified), I need to get a server that processes HTTP requests for PHP pages over FastCGI, to honour "Connection: Keep-alive" (sent by said client)...
- 116
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912
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socket_keepalive configuration for mod_jk
I have Apache httpd with mod_jk. I have issue with killed connections after long idling period: Apache stops to respond and each HTTP request hangs for 15 minutes. I tried turn off mod_jk connection ...
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1
answer
1k
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Linux GRE keep alive
What are possibilities in Linux kernel (?) to work with Cisco endpoint encorporating GRE keep-alives? We have GRE IPsec tunnel set up with another company. We would like to have backup tunnel which ...
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2
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3k
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KeepAlive in Apache 2.4 interfering with form submissions
I have just upgraded a server to Debian Jessie, which includes Apache 2.4.10 (was 2.2), and PHP 5.6.
Now, SSL sites won't submit forms in some circumstances on IE11 and iPad Safari (not sure about ...
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2
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2k
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Keeping TCP connections alive to track which clients are online
I am developing an application where a server needs to stay in touch with lots of simple IoT devices. Nearly no information exchange is needed between the server and each device, but devices need to ...
- 123
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1
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1k
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TCP Keepalive: Why does an idled ESTABLISHED connection end after 60 seconds, instead of tcp_keepalive_time?
I am investigating ways to mitigate a server against DoS-type attacks. In one scenario, I've opened several hundred TCP connections to my webserver. I do not send any data after the initial TCP ...
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379
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WebSphere breaks connection while servlet continues to work
We have an application running on WebSphere. Requests are often running for a long time (tens of minutes). Our users report that Internet Explorer breaks connection and shows blank screen after some ...
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1k
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Keepalived + Haproxy performance, apache or nginx? [duplicate]
I have a question about Keepalived + Haproxy. At work I am assigned to deploy a redundant web server with Keepalived and Haproxy. Our setup at the moment is as follows:
Apache (as load balancer) + ...
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6
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2
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2k
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(Why) does FreeBSD 'net.inet.tcp.always_keepalive' violate RFC1122?
While working on a server application that runs on FreeBSD and uses TCP, I noticed that TCP keepalive probes get
sent even though my application explicitly disables SO_KEEPALIVE on TCP sockets.
...
2
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0
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13k
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HAProxy resetting backend connections
I'm in the process of setting up a series of servers as proxies to our application server, primarily to obscure the application server's IP as part of a suite of anti-DDOS measures.
My goal is to ...
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2k
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Keepalive best practices for Nginx-Haproxy-Apache chain
I am using Nginx to serve static content, and Haproxy to proxy requests to multiple Apache2 backends discovered via Zookeeper.
Nginx -> Haproxy -> Apache2
According to the official Nginx website, it ...
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1
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3k
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How does apache handles connections and requests using worker and prefork mpm modules?
I know that prefork module in apache creates one master process and several child processes to handle connections, my question is:
Does each prefork child handles one connection or handles one ...
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1k
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Configure Server to Initiate Http Keep-Alive
I have a set of clients that aren't including an http keep-alive header in their requests to my server. If I use something like Varnish to filter the incoming requests and add the keep-alive header ...
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40k
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Haproxy - timeout http-request vs timeout http-keep-alive vs timeout server
I'm trying to wrap my head around how the haproxy options
timeout http-request <timeout>
timeout http-keep-alive <timeout>
timeout server <timeout>
interact with each other. I'm ...
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1
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1k
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HTTP connection keepalive logic [closed]
I am fairly new to HTTP and pardon me if the question looks stupid.
I cant get my head around the HTTP keepalive logic.
I am studying HTTP definitive guide.
We send multiple requests , response over ...
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8k
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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. server.max-...
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893
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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 ...
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