diff --git a/nginx.conf b/nginx.conf
index fef3336..d526c75 100644
--- a/nginx.conf
+++ b/nginx.conf
@@ -213,6 +213,9 @@ echo "Docker configured with HTTPS_PROXY=$scheme://$http_host/"
         # Add the authentication info, if the map matched the target domain.
         proxy_set_header Authorization $finalAuth;
 
+        # Use SNI during the TLS handshake with the upstream.
+        proxy_ssl_server_name on;
+
         # This comes from a include file generated by the entrypoint.
         include /etc/nginx/docker.verify.ssl.conf;