Comments on: High-availability Drupal — File-handling http://www.adamfranco.com/2009/09/09/high-availability-drupal-file-handling/ Musings, projects, software, and photography. Sun, 22 Jan 2012 19:17:45 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Adam Franco http://www.adamfranco.com/2009/09/09/high-availability-drupal-file-handling/#comment-141 Adam Franco Sat, 21 Nov 2009 18:43:38 +0000 http://www.adamfranco.com/?p=266#comment-141 Hi JJ, We are currently just using round-robin DNS where the the DNS responses include all of the IP addresses of the web servers, but rotate which one is listed first. If the host listed first is down, clients will generally try the next host in the list after a timeout period. While this can cause a large decrease in response time when a host goes down, it does provide fail-over abilities without having to add a dedicated load-balancer in front of the web servers. I'll post an update if we ever change this set-up, but I doubt that we will ever need to scale to the point where uneven webserver load becomes our pain-point. - Adam Hi JJ,

We are currently just using round-robin DNS where the the DNS responses include all of the IP addresses of the web servers, but rotate which one is listed first.

If the host listed first is down, clients will generally try the next host in the list after a timeout period. While this can cause a large decrease in response time when a host goes down, it does provide fail-over abilities without having to add a dedicated load-balancer in front of the web servers.

I’ll post an update if we ever change this set-up, but I doubt that we will ever need to scale to the point where uneven webserver load becomes our pain-point.

- Adam

]]> By: JJ http://www.adamfranco.com/2009/09/09/high-availability-drupal-file-handling/#comment-140 JJ Wed, 18 Nov 2009 02:26:45 +0000 http://www.adamfranco.com/?p=266#comment-140 Nice article and illustrations. However, one point I did not see you address was how to handle and manage the DNS requests for load balancing? Are you assuming a round robin approach? Would like to hear your thoughts on this. Thx, JJ Nice article and illustrations. However, one point I did not see you address was how to handle and manage the DNS requests for load balancing? Are you assuming a round robin approach? Would like to hear your thoughts on this.

Thx,
JJ

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