Ошибка upstream sent too big header while reading response header from upstream

I am getting these kind of errors:

2014/05/24 11:49:06 [error] 8376#0: *54031 upstream sent too big header while reading response header from upstream, client: 107.21.193.210, server: aamjanata.com, request: «GET /the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https://aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20https:/aamjanata.com/the-brainwash-chronicles-sponsored-by-gujarat-government/,%20ht

Always it is the same. A url repeated over and over with comma separating. Can’t figure out what is causing this. Anyone have an idea?

Update: Another error:

http request count is zero while sending response to client

Here is the config. There are other irrelevant things, but this part was added/edited

fastcgi_cache_path /var/nginx-cache levels=1:2 keys_zone=WORDPRESS:100m inactive=60m;
fastcgi_cache_key "$scheme$request_method$host$request_uri";
fastcgi_cache_use_stale error timeout invalid_header http_500;
fastcgi_ignore_headers Cache-Control Expires Set-Cookie;
proxy_buffer_size   128k;
proxy_buffers   4 256k;
proxy_busy_buffers_size   256k;
    # Upstream to abstract backend connection(s) for PHP.
    upstream php {
            #this should match value of "listen" directive in php-fpm pool
            server unix:/var/run/php5-fpm.sock;
    }

And then in the server block:
set $skip_cache 0;

    # POST requests and urls with a query string should always go to PHP
    if ($request_method = POST) {
            set $skip_cache 1;
    }
    if ($query_string != "") {
            set $skip_cache 1;
    }

    # Don't cache uris containing the following segments
    if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|/feed/|index.php|sitemap(_index)?.xml") {
            set $skip_cache 1;
    }

    # Don't use the cache for logged in users or recent commenters
    if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_no_cache|wordpress_logged_in") {
            set $skip_cache 1;
    }

    location / {
            # This is cool because no php is touched for static content.
            # include the "?$args" part so non-default permalinks doesn't break when using query string
            try_files $uri $uri/ /index.php?$args;
    }


    location ~ .php$ {
            try_files $uri /index.php;
            include fastcgi_params;
            fastcgi_pass php;
            fastcgi_read_timeout 3000;

            fastcgi_cache_bypass $skip_cache;
            fastcgi_no_cache $skip_cache;

            fastcgi_cache WORDPRESS;
            fastcgi_cache_valid  60m;
    }

    location ~ /purge(/.*) {
        fastcgi_cache_purge WORDPRESS "$scheme$request_method$host$1";
    }`

Faced the same problem when running Symfony app in php-fpm and nginx in docker containers.

After some research found that it was caused by php-fpm’s stderr written to nginx logs. I.e. php warnings (which is generated intensively in Symfony debug mode) was duplicated in docker logs php-fpm:

[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: "NOTICE: PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelEventListenerDisallowRobotsIndexingListener::onResponse"."
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: "NOTICE: PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelEventListenerStreamedResponseListener::onKernelResponse"."
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: "NOTICE: PHP message: [debug] Notified event "kernel.finish_request" to listener "SymfonyComponentHttpKernelEventListenerLocaleListener::onKernelFinishRequest"."
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: "NOTICE: PHP message: [debug] Notified event "kernel.finish_request" to listener "SymfonyComponentHttpKernelEventListenerRouterListener::onKernelFinishRequest"."
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: "NOTICE: PHP message: [debug] Notified event "kernel.finish_request" to listener "SymfonyComponentHttpKernelEventListenerLocaleAwareListener::onKernelFinishRequest"."
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: "NOTICE: PHP message: [debug] Notified event "kernel.terminate" to listener "SymfonyComponentHttpKernelEventListenerProfilerListener::onKernelTerminate"."
[09-Jul-2021 12:25:46] WARNING: [pool www] child 38 said into stderr: ""

and docker logs nginx:

2021/07/09 12:25:46 [error] 30#30: *2 FastCGI sent in stderr: "ller" to listener "OblgazAPIAPICommonInfrastructureEventSubscriberLegalAuthenticationChecker::checkAuthentication".

PHP message: [debug] Notified event "kernel.controller_arguments" to listener "SymfonyComponentHttpKernelEventListenerErrorListener::onControllerArguments".

PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelEventListenerResponseListener::onKernelResponse".

PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelDataCollectorRequestDataCollector::onKernelResponse".

PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelEventListenerProfilerListener::onKernelResponse".

PHP message: [debug] Notified event "kernel.response" to listener "SymfonyBundleWebProfilerBundleEventListenerWebDebugToolbarListener::onKernelResponse".

PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelEventListenerDisallowRobotsIndexingListener::onResponse".

PHP message: [debug] Notified event "kernel.response" to listener "SymfonyComponentHttpKernelEventListenerStreamedResponseListener::onKernelResponse".

PHP message: [debug] Notified event "kernel.finish_request" to listener "SymfonyComponentHttpKernelEventListenerLocaleListener::onKernelFinishRequest".

PHP message: [debug] Notified event "kernel.finish_request" to listener "SymfonyComponentHttpKernelEventListenerRouterListener::onKernelFinishRequest".

PHP message: [debug] Notified event "kernel.finish_request" to listener "SymfonyComponentHttpKernelEventListenerLocaleAwareListener::onKernelFinishRequest".

PHP message: [debug] Notified event "kernel.exception" to listener "SymfonyComponentHttpKernelEventListenerErrorListener::logKernelException".

PHP message: [debug] Notified event "kernel.exception" to listener "SymfonyComponentHttpKernelEventListenerProfilerListener::onKernelException".

and then nginx logs ended with

2021/07/09 12:25:46 [error] 30#30: *2 upstream sent too big header while reading response header from upstream ...

and I got 502 error.

Increasing the fastcgi_buffer_size in nginx config helped, but it seems more like a suppression the problem, not a treatment.

A better solution is to disable php-fpm to send logs by FastCGI. Found it can be made by setting fastcgi.logging=0 in php.ini (by default it is 1). php docs.

After changing it to 0, the problem goes away and nginx logs looks much cleaner docker logs nginx:

172.18.0.1 - - [09/Jul/2021:12:36:02 +0300] "GET /my/symfony/app HTTP/1.1" 401 73 "-" "PostmanRuntime/7.26.8"
172.18.0.1 - - [09/Jul/2021:12:36:04 +0300] "GET /my/symfony/app HTTP/1.1" 401 73 "-" "PostmanRuntime/7.26.8"

and all php-fpm logs are still in their place in php-fpm log.

answered Jul 9, 2021 at 10:06

This is still the highest SO-question on Google when searching for this error, so let’s bump it.

When getting this error and not wanting to deep-dive into the NGINX settings immediately, you might want to check your outputs to the debug console.
In my case I was outputting loads of text to the FirePHP / Chromelogger console, and since this is all sent as a header, it was causing the overflow.

It might not be needed to change the webserver settings if this error is caused by just sending insane amounts of log messages.

answered Dec 19, 2019 at 9:24

I am not sure that the issue is related to what header php is sending.
Make sure that the buffering is enabled. The simple way is to create a proxy.conf file:

proxy_redirect          off;
proxy_set_header        Host            $host;
proxy_set_header        X-Real-IP       $remote_addr;
proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
client_max_body_size    100m;
client_body_buffer_size 128k;
proxy_connect_timeout   90;
proxy_send_timeout      90;
proxy_read_timeout      90;
proxy_buffering         on;
proxy_buffer_size       128k;
proxy_buffers           4 256k;
proxy_busy_buffers_size 256k;

And a fascgi.conf file:

fastcgi_param  SCRIPT_FILENAME    $document_root$fastcgi_script_name;
fastcgi_param  QUERY_STRING       $query_string;
fastcgi_param  REQUEST_METHOD     $request_method;
fastcgi_param  CONTENT_TYPE       $content_type;
fastcgi_param  CONTENT_LENGTH     $content_length;
fastcgi_param  SCRIPT_NAME        $fastcgi_script_name;
fastcgi_param  REQUEST_URI        $request_uri;
fastcgi_param  DOCUMENT_URI       $document_uri;
fastcgi_param  DOCUMENT_ROOT      $document_root;
fastcgi_param  SERVER_PROTOCOL    $server_protocol;
fastcgi_param  GATEWAY_INTERFACE  CGI/1.1;
fastcgi_param  SERVER_SOFTWARE    nginx/$nginx_version;
fastcgi_param  REMOTE_ADDR        $remote_addr;
fastcgi_param  REMOTE_PORT        $remote_port;
fastcgi_param  SERVER_ADDR        $server_addr;
fastcgi_param  SERVER_PORT        $server_port;
fastcgi_param  SERVER_NAME        $server_name;
fastcgi_buffers 128 4096k;
fastcgi_buffer_size 4096k;
fastcgi_index  index.php;
fastcgi_param  REDIRECT_STATUS    200;

Next you need to call them in your default config server this way:

http {
  include    /etc/nginx/mime.types;
  include    /etc/nginx/proxy.conf;
  include    /etc/nginx/fastcgi.conf;
  index    index.html index.htm index.php;
  log_format   main '$remote_addr - $remote_user [$time_local]  $status '
    '"$request" $body_bytes_sent "$http_referer" '
    '"$http_user_agent" "$http_x_forwarded_for"';
  #access_log   /logs/access.log  main;
  sendfile     on;
  tcp_nopush   on;
 # ........
}

answered Apr 23, 2020 at 15:05

For Symfony projects, try adding this line to your .env file:

SHELL_VERBOSITY=0

https://symfony.com/doc/current/console/verbosity.html

I will just leave it here, because I spent a crazy amount of time debugging this in my project and only this particular solution worked 100% for me (for the right reasons) and I have never found this answer related to this topic. Maybe someone will find it helpful.

answered Sep 24, 2021 at 21:28

I am using Symfony, it has a nice exception page (when the ErrorHandler is used). And this one will put the message of your exception as a header to the response created.

vendor/symfony/error-handler/ErrorRenderer/SerializerErrorRenderer.php

the header is called: X-Debug-Exception

So be careful, if you constructed a VERY large exception message, neither nginx nor chrome (limit 256k) nor curl (~128kb) can display your page and make it really hard to debug, what is outputting those big headers.

My suggestion would be to not blindly copy n paste increased buffer sizes into your nginx config, they treat the symptom not the cause.

answered May 5, 2022 at 4:46