PHP-FPM 不写入错误日志

我刚刚安装了一个nginx + php-fpm服务器。一切似乎都很好，除了PHP-FPM从不将错误写入其日志。

fpm.conf

[default]
listen = /var/run/php-fpm/default.sock
listen.allowed_clients = 127.0.0.1
listen.owner = webusr
listen.group = webusr
listen.mode = 0666
user = webusr
group = webusr
pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35
pm.status_path = /php/fpm/status
ping.path = /php/fpm/ping
request_terminate_timeout = 30s
request_slowlog_timeout = 10s
slowlog = /var/log/php-fpm/default/slow.log
chroot = /var/www/sites/webusr
catch_workers_output = yes
env[HOSTNAME] = mapsvr.mapking.com
php_flag[display_errors] = on
php_admin_value[error_log] = /var/log/php-fpm/default/error.log
php_admin_flag[log_errors] = on

nginx.conf

server
{
  listen        80 default_server;
  server_name   _;

  charset       utf-8;
  access_log    /var/log/nginx/access.log rest;

  include       conf.d/drops.conf.inc;

  location      /
  {
    root        /var/www/sites/webusr/htdocs;
    index       index.html index.htm index.php;
  }

  # pass the PHP scripts to FastCGI server listening on socket
  #
  location      ~ \.php$
  {
    root           /var/www/sites/webusr/htdocs;
    include        /etc/nginx/fastcgi_params;
    fastcgi_index  index.php;
    fastcgi_param  SCRIPT_FILENAME /htdocs/$fastcgi_script_name;
    if (-f $request_filename)
    {
      fastcgi_pass   unix:/var/run/php-fpm/default.sock;
    }
  }

  location      = /php/fpm/status
  {
    include        /etc/nginx/fastcgi_params;
    fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;
    fastcgi_pass   unix:/var/run/php-fpm/default.sock;
  }

  location      = /php/fpm/ping
  {
    include        /etc/nginx/fastcgi_params;
    fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;
    fastcgi_pass   unix:/var/run/php-fpm/default.sock;
  }

  # redirect server error pages to the static page /50x.html
  #
  error_page    500 502 503 504  /50x.html;
  location      = /50x.html
  {
    root        /usr/share/nginx/html;
  }
}

我制作了一个错误的php脚本并运行，并在Web浏览器上看到错误输出。此外，nginx错误日志声明来自fpm的stderr输出具有相同的消息。我已经检查用户是否对指定的日志文件夹具有写入（我甚至尝试过777）权限。即使是指定的错误.log文件也已通过php-fpm成功创建。但是，日志文件始终是空的，无论php脚本中犯了什么令人发指的错误。

这是怎么回事？

[很久以后才找到原因]

这是许可。将所有者更改为网站的用户解决了问题。