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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Layer 4 vs Layer 7 Load Balancing

I am trying to decide between using a layer 4 load balancing solution for my datacenter or a layer 7 solution. Unfortunately (for my sanity, that is), my use case is simple enough that both solutions would work well, avoiding most of the weaknesses…
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How can I deploy a scalable, reliable haproxy cluster on Amazon EC2?

We need some more advanced functionality than ELB provides (mostly L7 inspection), but it's not obvious how to handle things like heartbeat and high availability with something like haproxy using EC2. There's a high likelihood we'd need 3 or more…
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How is a single IP address load balanced?

I'm aware of "round robin DNS" load balancing, but how can a single IP address be load balanced? Google's DNS servers for example, 8.8.8.8 and 8.8.4.4. Wikipedia's load balancing article states: For Internet services, the load balancer is usually…
Torvero
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Load-balancer options

I am looking at a number of possible options for load-balancing. So far, I am constrained to the following options: DNS server load-balancer, balancing to a cluster of tomcat servers, with terracotta for session replication. Pros - don't have to…
toolkit
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How do I Install Intermediate Certificates (in AWS)?

I have installed private key (pem encoded) and public key certificate (pem encoded) on Amazon Load Balancer. However, when I check the SSL with site test tool, I get the following error: Error while checking the SSL Certificate!! Unable to get the…
getmizanur
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LVS vs HAProxy, which should I choose?

I am looking for a solution to load balancing and failover strategy, mainly for big web applications. We have many services to be balanced, such as web, MySQL, and many other HTTP or TCP based services. But I am not sure what their pros and cons…
Mickey Shine
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nginx failover without load balancing

I'm having trouble configuring nginx. I'm using nignx as a reverse proxy. I want to send my all requests to my first server. If the first server is down, I want to send requests to second server. In short, how can I have a failover solution without…
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How can I use HAproxy with SSL and get X-Forwarded-For headers AND tell PHP that SSL is in use?

I have the following setup: (internet) ---> [ pfSense Box ] /-> [ Apache / PHP server ] [running HAproxy] --+--> [ Apache / PHP server ] +--> [ Apache / PHP server ] …
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Keepalive setting for Gunicorn behind ELB without Nginx

Our app's REST API is served by Gunicorn (not behind Nginx) running on AWS EC2 instances with a typical auto-scaling/load balancing setup. The load balancer's idle timeout is 60 seconds, and Gunicorn's keep-alive timeout is 2 seconds. We've been…
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Redirect all HTTP traffic to HTTPS when using the HTTP(S) Load Balancer on Google Compute Engine

I have HTTP/HTTPS Load Balancing set up on Google Compute Engine with 2 Global Forwarding Rules (HTTP and HTTPS). Each rule points to a back-end service with a protocol of HTTP. I want all requests to http://* to go to https://*. As the load…
Ryan Leckey
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Outlook fails to connect to a load-balanced Exchange 2013 cluster through Direct Access 2012 R2

We have a load-balanced Exchange 2013 SP1 cluster, running MAPI over HTTP. Client connectivity inside our own network works just fine, while clients connected over Direct Access does not connect. The Outlook logs on the client show absolutely no…
pauska
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EC2 Update my existing AMI

I'm using Elastic Load Balancing to load balance my Auto Scaling Group, for that I have a private AMI that hold my application server (Tomcat) and my web app deployed to it as war ... Now everything works fine ... what if I need to change my tomcat…
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Issues with EC2 Elastic Load Balancer DNS and routing

We're trying to run a fairly straightforward setup on Amazon EC2 - several HTTP servers sitting behind an Amazon Elastic Load Balancer (ELB). Our domain is managed in Route53, and we have a CNAME record set up to point to the ELB. We've experienced…
Cera
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Software http load balancer?

Right now we only have one back-end server per site/web service. I'd be interested to hear people's experiences with various load balancer apps (something that runs on Linux). What would you recommend?
Mark Renouf
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When using TCP load balancing with HAProxy, does all outbound traffic flow through the LB?

I am setting up an app to be hosted using VMs(probably amazon, but that is not set in stone) which will require both HTTP load balancing and load balancing a large number(50k or so if possible) of persistant TCP connections. The amount of data is…
user122875
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