What does ERR_SPDY_PROTOCOL_ERROR mean in nginx?

Question

I and a few of my colleagues got the net::ERR_SPDY_PROTOCOL_ERROR error.

We use ngnix version 1.8.0. The error is not stable (hard to replicate), and t

Answer 1

I came across this question when trying to find help for the problem I was facing with ERR_SPDY_PROTOCOL_ERROR on Chrome. Thought this might benefit others.

Our situation / solution: We use an AWS Application Load Balancer connected to EC2 instances. One of the scripts we run on EC2 proxies requests from the client browser. We recently updated the script - no relevant changes - and noticed that both Chrome and Safari requests to the proxy script started failing. Chrome showed the ERR_SPDY_PROTOCOL_ERROR error and, when we dug in to it, we could see this request was using HTTP/2. Firefox requests continued to work fine.

Our solution: we switched off HTTP/2 support in the ALB. Immediately solved the problem.

AWS CLI command:

aws elbv2 modify-load-balancer-attributes --load-balancer-arn  --attributes Key=routing.http2.enabled,Value=false