Http on Evan Hoffman

Rails app redirects to wrong port?

Fri, 28 Mar 2014 15:17:30 +0000

Ran into a situation in which a rails application was redirecting to /login to force a user to log in, but the Location header said “http://site.com:8085/login", because nginx was listening on port 8085 on that server. At first I looked to see if there was something in the application code that was doing this, or maybe some setting I could change to fix it, but came up blank. After some Googling I found the answer right in the Nginx docs (below is my slightly-modified solution that handles https urls as well):

Slow HTTP downloads through Cisco ASA 5500

Tue, 28 Feb 2012 16:15:20 +0000

Recently we noticed weird behavior downloading files from certain sites. The transfer would start out fast (around 10 MB/s), then after a couple of seconds it would plummet to around 9 KB/s. It didn’t happen for every file or every site: downloads from S3 buckets were still particularly fast. But some files that I remember being particularly fast were now showing this weird fast/slow/fast/slow behavior, for example the Sun JDK and ISOs from rit.edu that used to saturate our pipe were now getting all cRAzY.

Load balancing in EC2 with Nginx and HAProxy

Mon, 09 Jan 2012 17:00:22 +0000

We wanted to setup a loadbalanced web cluster in AWS for expansion. My first inclination was to use ELB for this, but I soon learned that ELB doesn’t let you allocate a static IP, requiring you to refer to it only by DNS name. This would be OK except for the fact that our current DNS provider, Dyn, requires IP addresses when using their GSLB (geo-based load balancer) service.

Rather than let this derail the whole project, I decided to look into the software options available for loadbalancing in EC2. I’ve been a fan of hardware load balancers for a while, sort of looking down at software-based solutions without any real rationale, but in this case I really had no choice so I figured I’d give it a try.