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Questions tagged [load-balancing]

Load balancing deal with the techniques involved on using multiple systems to deal with high demands, balancing the load between those multiple systems. Questions deal with networking and server load balancing, using dedicated hardware or not.

Load balancing is a group of techniques used to ensure that loads are spread between multiple systems. The term is used on networking and server environments, with similar results.

Network load balancing involves using multiple connections or links to spread speed or high demand between those connections. That can be done on backbone links, carrier internet links or even from servers to switches to provide more speed using link sharing.

Server load balancing utilizes hardware (hardware load balancers) or software (software load balancers) to spread the requests destined for a domain or system between various servers behind those load balancers (often named backends). Load balancing ensures that high performance and scalability can be achieved by addition of servers.

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What is the difference between Load Balancer and Reverse Proxy?

I'm not clear about the difference between Load Balancer and Reverse Proxy. They both seems having same behavior: distributing incoming requests to backend servers.
Morgan Cheng
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Does each server behind a load balancer need their own SSL certificate?

If you have 5 web servers behind a load balancer (such as haproxy) and they are serving up content for the same domain, do you need SSL certificates for all the servers, or can you use the same certificate on each server? I know you can put all SSL…
Derek Gathright
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Is Round-Robin DNS "good enough" for load balancing static content?

We have a set of shared, static content that we serve up between our websites at http://sstatic.net. Unfortunately, this content is not currently load balanced at all -- it's served from a single server. If that server has problems, all the sites…
Jeff Atwood
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How can I remove balanced node from haproxy via command line?

I have haproxy running as my load-balancer and from the stats web interface that comes with haproxy, I can put a web server into maintenance mode (and bring it back out again) - which is great! However, I also want to be able to perform that same…
isNaN1247
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How to set up stats for HAProxy?

I can't figure out how to set up stats for HAProxy. This is my configuration: global log 127.0.0.1 local0 log 127.0.0.1 local1 notice daemon #debug user haproxy group haproxy maxconn 4096 stats socket…
Jan Deinhard
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How to make redundant load balancers?

I understand that the purpose of load balancers is to balance load between your servers and keep track of instance health, etc. But what if load balancer itself fails? How do you set up redundant load balancers? (load balancing load balancers?) I…
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Point multiple IP addresses to a single host name

In Windows System, there is this file at C:\WINDOWS\system32\drivers\etc\hosts. This file allows us to default a specific IP address to a host name. The issue now is whether I can set multiple IP addresses to a host name. For example, can I do…
Graviton
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What is a typical method to scale out a software load balancer?

I often see web app architectures with a SLB / reverse-proxy in front of a bunch of app servers. What happens when the number of connections to the SLB requires too many resources for a single SLB to handle effectively? For a concrete yet…
z8000
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What kind of load balancing algorithms are there

I was researching different load balancing algorithms for HTTP and I just found 3. Random, Round Robin and Weighted Round Robin. Are there any other options? Thanks Paul
Paul Sheldrake
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Do HTTP reverse proxies typically enable HTTP Keep-Alive on the client side of the proxied connection and not on the server side?

HAProxy has the ability to enable HTTP keep-alive on the client side (client <-> HAProxy) but disable it on the server side (HAProxy <-> server). Some of our clients connect to our web service via satellite so the latency is ~600ms and I think that…
LostInComputer
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nginx automatic failover load balancing

I'm using nginx and NginxHttpUpstreamModule for loadbalancing. My config is very simple: upstream lb { server 127.0.0.1:8081; server 127.0.0.1:8082; } server { listen 89; server_name localhost; location / { …
robinmag
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What are the Differences between HAProxy and Ngnix in reverse proxy mode?

What are the differences between HAProxy and Nginx when it comes to their abilities as a reverse proxy?
Quintin Par
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HAProxy reqrep remove URI on backend request

real quick question regarding HAProxy reqrep. I am trying to rewrite/replace the request that gets sent to the backend. I have the following example domain and URIs, both sharing the same domain name, but different backend web server…
Jim
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nginx: [emerg] "stream" directive is not allowed here

I have the latest NGINX from ppa installed on Ubuntu 16.04. nginx version: nginx/1.12.1 From my understanding, it should support stream and UDP load balancing. But I get this error message: nginx: [emerg] "stream" directive is not allowed here in…
Houman
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Hardware vs Software load balancers: Just a cost issue?

If cost were not an issue, would there be any benefit in deploying a software load balancer for web traffic compared to a hardware one?
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