Amazon EC2 Web server in Load Balancer gives 503
- by dale
we've been running our web servers at Amazon with load balancer and auto-scaling for over a year with no problem. All of a sudden today the request began to get aborted with the error:
503 ... Backend server is at capacity
The web servers are at 1% CPU and no other alarms trigger.
We use Amazons load balancer and nginx.
Lots of requests like this are showing up in the access_log.
10.246.114.93 - - [05/Jun/2014:20:16:09 +0000] "-" 400 0 "-" "-"
10.246.114.93 - - [05/Jun/2014:20:16:09 +0000] "-" 400 0 "-" "-"
10.246.114.93 - - [05/Jun/2014:20:16:09 +0000] "-" 400 0 "-" "-"
10.246.114.93 - - [05/Jun/2014:20:16:09 +0000] "-" 400 0 "-" "-"
10.246.114.93 - - [05/Jun/2014:20:16:10 +0000] "-" 400 0 "-" "-"
10.246.114.93 - - [05/Jun/2014:20:16:10 +0000] "-" 400 0 "-" "-"
10.246.114.93 - - [05/Jun/2014:20:16:10 +0000] "-" 400 0 "-" "-"
10.229.15.214 - - [05/Jun/2014:20:16:10 +0000] "-" 400 0 "-" "-"
10.229.15.214 - - [05/Jun/2014:20:16:10 +0000] "-" 400 0 "-" "-"
Any thoughts?