Hello, I am using nginx on a VPS to proxy requests to a GCP server. When working with IPv4, everything works as desired. However, if we enable IPv6 on client machine, we see that the first call (/auth) fails with 401, and all subsequent calls are successful. We cannot see the first call on GCP. I have made sure that AAAA records do exist, GCP endpoint supports IPv6. This is my configuration for Nginx (some values redacted).
server { listen 80; listen [::]:80; server_name xxxxx.us www.xxxxx.us; location / { return 301 https://xxxxx.us$request_uri; } } server { listen 443 ssl http2; listen [::]:443 ssl http2; server_name xxxxx.us www.xxxxx.us; root /var/www/xxxxx.us/html; index index.html; # SSL ssl_certificate fullchain.pem; ssl_certificate_key privkey.pem; ssl_trusted_certificate chain.pem; # Security include options-ssl-nginx.conf; ssl_dhparam ssl-dhparams.pem; client_max_body_size 10M; location / { proxy_pass https://xxxxx.appspot.com/; } location /gcp/ { proxy_pass https://xxxxx.appspot.com/; } Proxy pass /gcp/ is the one we are using for redirecting to GCP. I am always getting the first call as 401, but second call (same), succeeds. Please let me know if you have seen this before and what I can change to fix this. Also, just to reiterate, if we disable IPv6 on the calling machine, there are no issues. Logs (two subsequent calls): "POST /gcp/users/auth HTTP/2.0" 401 0 "http://localhost:3000/" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.11 0 Safari/537.36" "POST /gcp/users/auth HTTP/2.0" 200 606 "http://localhost:3000 /" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664. 110 Safari/537.36" Thanks. Posted at Nginx Forum: https://forum.nginx.org/read.php?2,293266,293266#msg-293266 _______________________________________________ nginx mailing list nginx@nginx.org http://mailman.nginx.org/mailman/listinfo/nginx