Nginx Retry of Requests ( Nginx - Haproxy Combination )
- by vaibhav
I wanted to ask about Nginx Retry of Requests. I have a Nginx running at the backend which then sends the requests to HaProxy which then passes it on the web server and the request is processed. I am reloading my Haproxy config dynamically to provide elasticity. The problem is that the requests are dropped when I reload Haproxy. So I wanted to have a solution where I can just retry that from Nginx. I looked through the proxy_connect_timeout, proxy_next_upstream in http module and max_fails and fail_timeout in server module. I initially only had 1 server in the upstream connections so I just that up twice now and less requests are getting dropped ( only when ) have say the same server twice in upstream , if I have same server 3-4 times drops increase ).
So , firstly I wanted to now , that when a request is not able to establish connection from Nginx to Haproxy so while reloading it seems that conneciton is seen as error and straightway the request is dropped .
So how can I either specify the time after the failure I want to retry the request from Nginx to upstream or the time before which Nginx treats it as failed request.
( I have tried increaing proxy_connect_timeout - didn't help , mail_retires , fail_timeout and also putting the same upstream server twice ( that gave the best results so far )
Nginx Conf File
upstream gae_sleep {
server 128.111.55.219:10000;
}
server {
listen 8080;
server_name 128.111.55.219;
root /var/apps/sleep/app;
# Uncomment these lines to enable logging, and comment out the following two
#access_log /var/log/nginx/sleep.access.log upstream;
error_log /var/log/nginx/sleep.error.log;
access_log off;
#error_log /dev/null crit;
rewrite_log off;
error_page 404 = /404.html;
set $cache_dir /var/apps/sleep/cache;
location / {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
proxy_pass http://gae_sleep;
client_max_body_size 2G;
proxy_connect_timeout 30;
client_body_timeout 30;
proxy_read_timeout 30;
}
location /404.html {
root /var/apps/sleep;
}
location /reserved-channel-appscale-path {
proxy_buffering off;
tcp_nodelay on;
keepalive_timeout 55;
proxy_pass http://128.111.55.219:5280/http-bind;
}
}
