Better handling of late upstream creation. Configuration with duplicate upstream blocks defined after first use, i.e. like server { ... location / { proxy_pass http://backend; } } upstream backend { ... } upstream backend { ... } now correctly results in "duplicate upstream" error. Additionally, upstream blocks defined after first use now handle various server directive parameters ("weight", "max_fails", etc.). Previously configuration like server { ... location / { proxy_pass http://backend; } } upstream backend { server 127.0.0.1 max_fails=5; } incorrectly resulted in "invalid parameter "max_fails=5"" error.