diff --git a/admin_manual/installation/nginx-root.conf.sample b/admin_manual/installation/nginx-root.conf.sample
index c0f62e19609..96fe49ec8d1 100644
--- a/admin_manual/installation/nginx-root.conf.sample
+++ b/admin_manual/installation/nginx-root.conf.sample
@@ -56,6 +56,13 @@ server {
     client_body_timeout 300s;
     fastcgi_buffers 64 4K;
 
+    # avoid 502 at root URL due to too large header response
+    proxy_busy_buffers_size 512k;
+    proxy_buffers 4 512k;
+    proxy_buffer_size 256k;
+    fastcgi_buffer_size 64k;
+    fastcgi_busy_buffers_size 64k;
+
     # Proxy and client response timeouts
     # Uncomment an increase these if facing timeout errors during large file uploads
     #proxy_connect_timeout 60s;
diff --git a/admin_manual/installation/nginx-subdir.conf.sample b/admin_manual/installation/nginx-subdir.conf.sample
index 4f962b0ace0..ab211a08870 100644
--- a/admin_manual/installation/nginx-subdir.conf.sample
+++ b/admin_manual/installation/nginx-subdir.conf.sample
@@ -82,6 +82,13 @@ server {
         client_body_timeout 300s;
         fastcgi_buffers 64 4K;
 
+        # avoid 502 at root URL due to too large header response
+        proxy_busy_buffers_size 512k;
+        proxy_buffers 4 512k;
+        proxy_buffer_size 256k;
+        fastcgi_buffer_size 64k;
+        fastcgi_busy_buffers_size 64k;
+
         # Proxy and client response timeouts
         # Uncomment an increase these if facing timeout errors during large file uploads
         #proxy_connect_timeout 60s;