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Does having a load balancer allow you to re-use socket connections?

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http://serverfault.com – I have a service where servers upload 20kb xml files to my server. There is no session, it is a single POST request and that's it. Each individual request is authenticated based on the contents of the xml file. There are socket related tweaks that I will have to make as during load testing the server exhausts its sockets pool (32K). Anyhow, I was wondering what things might change when I bring a load balancer into the equation that would round robin requests between 2+ web servers. Could the load balancer re-use sockets? Again, just want to be clear, client servers are posting a file ove (HowTos)

xskl's picture
Submitted by xskl on 04/28/2012 – Made popular on 04/28/2012

Stories similar to Does having a load balancer allow you to re-use socket connections?

I am going to host few servers (MS-Windows) listening on certain port to which my clients would connect. I will have to have a load balancer to distribute connections amongst these servers. I have gathered knowledge about load balancer's and have learned few things. But I am not sure if my understanding is correct. Hence, sharing it here so that someone experienced can please verify the same?

We're building a load balanced setup with two load balancers (that also terminate SSL) and several upstream servers. Both the load balancers and the upstream servers run nginx. The network on which requests are forwarded to the upstream servers cannot be trusted, hence we have to re-encrypt it after SSL termination on the load balancer.

I have heard people say "oh that server is off the load balancer so you can run that expensive script on it".

What implications does a server off the load balancer have? Fundamental to answering this, I understand load balancing, but I don't know what the dynamics of a system with 5 servers (4 on the load balancer) has.

Thanks

When ever I try to load test a site that is load balanced on EC2 I get the following message:

ab -n 20 -c 20 http://www.somesite.com/

Benchmarking www.somesite.com (be patient)...Send request failed! apr_socket_recv: Connection reset by peer (54)

Any sites that are hosted on EC2 without the load balancer can be load tested successfully, so I figure it's not related to the security group I have

Imagine a load-balancer facing the internet, dispatching requests to several worker-servers in a local network.

Is there a way for the worker-servers to respond directly on the original socket / connection / IP or do they have to respond to the load-balancer for it to forward the response (making it the SPOF)?

If I set up a load balancer on aws that terminates ssl at the load balancer, then the requests being sent to the application server is in plain text. That has definite security implications. How do folks mitigate this implication in practice?

If alternatively, I set up https traffic between load balancer and the application servers also, what are the performance implications?

Our PHP application consists of a single web server that will receive files from clients and perform a CPU-intensive analysis on them. Right now, analysis of a single user upload can take 3sec to conclude and take 100% CPU. This makes our system capacity amount to 1/3 requests per second.

My team's requirement is to increase capacity without a lot of code reengineering.

Setting Up A High-Availability Load Balancer (With Failover and Session Support) With HAProxy/Heartbeat On Debian Lenny

I have 4 nginx-powered image servers on their own subdomains which users would access at random. I decided to put them all behind a HAProxy load balancer to improve the reliability and to see the traffic statistics from a single location.