Just hit this same issue, but the duplicate default_server directive was not the only cause of this message.
You can only use the backlog parameter on one of the server_name directives.
Example
site 1:1
2
3
4
5
6server {
listen 80 default_server backlog=2048;
server_name www.example.com;
location / {
proxy_pass http://www_server;
}
site 2:1
2
3
4
5
6server {
listen 80; ## NOT NOT DUPLICATE THESE SETTINGS 'default_server backlog=2048;'
server_name blogs.example.com;
location / {
proxy_pass http://blog_server;
}
backlog 只能在其中一个server上设置。
参考 https://stackoverflow.com/questions/13676809/serving-two-sites-from-one-server-with-nginx