I haven’t done it for sharepoint but I have done it for TFS. If I had to guess you are probably being bitten by NTLM.

NTLM authentication authenticates connections instead of requests, and this is somewhat contradicts HTTP protocol, which is expected to be stateless. As a result it doesn't generally work though proxies, including nginx.

NGINX can support it though, you need to use the "ntlm" directive. Below is an [stripped down] example of how I have it set up in front of TFS. I would think Sharepoint would be very similar. This has worked very reliably for like a year.

upstream MyNtlmService {
zone backend;
server 192.168.0.1:8080;
server 192.168.0.2:8080;
#See http://stackoverflow.com/questions/10395807/nginx-close-upstream-connection-after-request
keepalive 64;
#See http://nginx.org/en/docs/http/ngx_http_upstream_module.html#ntlm
ntlm;
}
server {
listen 80;

location / {
proxy_read_timeout 60s;
#http://stackoverflow.com/questions/21284935/nginx-reverse-proxy-with-windows-authentication-that-uses-ntlm
proxy_http_version 1.1;
proxy_set_header Connection "";

proxy_pass http:// MyNtlmService /;
}
}


Jason


-----Original Message-----
From: nginx [mailto:nginx-bounces@nginx.org] On Behalf Of blason
Sent: Friday, January 19, 2018 12:18 AM
To: nginx@nginx.org
Subject: [IE] Re: Has anyone implemented Nginx as a reverse proxy with Microsoft Sharepoint?

Wow man!! Thanks I am struggling with configuration as Subsites does not show anything it shows blank page i.e only for blank page while Front page gets open successfully.

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,278193,278195#msg-278195

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