我们遇到了一个非常严重的问题，在看似随机的时间，我们会收到由我们的应用程序处理的重复请求。通常，用户提交表单，有时会保存其内容两次。
我们已经排除了该问题是由 JS 驱动的重复提交的可能性。我们有一个网络分析器证明只发出了 1 个请求。但是，我们还证明 PHP 应用程序确实被完整地执行了两次。经过彻底调查，应用程序中不存在会导致这种重复保存行为的逻辑问题。
编辑：我们已从 NGINX conf 中删除“keepalive 8;”行，我们不再收到重复提交。相反，我们在有问题的请求期间收到 504
如果有人能看到下面的内容并发现任何突出之处，我将不胜感激 - 谢谢！
我们的 NGINX 和 PHP-FPM 配置如下：
/etc/nginx/nginx.conf
user nginx;
worker_processes 1;
worker_rlimit_nofile 10240;
error_log /var/log/nginx/error.log;
pid /var/run/nginx.pid;
events {
worker_connections 1024;
multi_accept on;
use epoll;
}
http {
server_tokens off;
add_header 'Access-Control-Allow-Origin' http://$host;
add_header 'Access-Control-Allow-Methods' 'GET, POST';
add_header 'X-Powered-By' 'smartCMS';
upstream php_fpm {
least_conn;
server 127.0.0.1:9000 max_fails=3 fail_timeout=15s;
keepalive 8;
}
include /etc/nginx/mime.types;
default_type application/octet-stream;
log_not_found off;
access_log /var/log/nginx/access.log combined buffer=16k;
open_file_cache max=200000 inactive=20s;
open_file_cache_valid 30s;
open_file_cache_min_uses 2;
open_file_cache_errors on;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_requests 200;
keepalive_timeout 65;
gzip on;
gzip_static on;
gzip_http_version 1.0;
gzip_comp_level 6;
gzip_proxied any;
gzip_types application/javascript application/x-javascript application/xhtml+xml application/xml application/xml+rss image/svg+xml text/css text/javascript text/plain text/xml;
gzip_vary on;
gzip_disable "MSIE [1-6].(?!.*SV1)";
client_max_body_size 12m;
client_body_buffer_size 128k;
client_body_timeout 60;
client_header_timeout 10;
large_client_header_buffers 4 16k;
send_timeout 60;
server_names_hash_bucket_size 64;
include /etc/nginx/conf.d/*.conf;
include /etc/nginx/sites-enabled/*;
}
/etc/php-fpm.conf
;;;;;;;;;;;;;;;;;;;;;
; FPM Configuration ;
;;;;;;;;;;;;;;;;;;;;;
; All relative paths in this configuration file are relative to PHP's install
; prefix.
; Include one or more files. If glob(3) exists, it is used to include a bunch of
; files from a glob(3) pattern. This directive can be used everywhere in the
; file.
include=/etc/php-fpm.d/pools/*.conf
;;;;;;;;;;;;;;;;;;
; PHP INI ;
;;;;;;;;;;;;;;;;;;
php_admin_value[upload_max_filesize] = 10M;
php_admin_value[post_max_size] = 12M;
php_admin_value[max_execution_time] = 60;
php_admin_value[expose_php] = Off;
;;;;;;;;;;;;;;;;;;
; Global Options ;
;;;;;;;;;;;;;;;;;;
[global]
; Pid file
; Default Value: none
pid = /var/run/php-fpm/php-fpm.pid
; Error log file
; Default Value: /var/log/php-fpm.log
error_log = /var/log/php-fpm/error.log
; Log level
; Possible Values: alert, error, warning, notice, debug
; Default Value: notice
log_level = warning
; If this number of child processes exit with SIGSEGV or SIGBUS within the time
; interval set by emergency_restart_interval then FPM will restart. A value
; of '0' means 'Off'.
; Default Value: 0
emergency_restart_threshold = 1
; Interval of time used by emergency_restart_interval to determine when
; a graceful restart will be initiated. This can be useful to work around
; accidental corruptions in an accelerator's shared memory.
; Available Units: s(econds), m(inutes), h(ours), or d(ays)
; Default Unit: seconds
; Default Value: 0
emergency_restart_interval = 1m
; Time limit for child processes to wait for a reaction on signals from master.
; Available units: s(econds), m(inutes), h(ours), or d(ays)
; Default Unit: seconds
; Default Value: 0
process_control_timeout = 60s
; Send FPM to background. Set to 'no' to keep FPM in foreground for debugging.
; Default Value: yes
daemonize = yes
;;;;;;;;;;;;;;;;;;;;
; Pool Definitions ;
;;;;;;;;;;;;;;;;;;;;
; See /etc/php-fpm.d/pools/*.conf
/etc/php-fpm.d/pools/www0.conf
; Start a new pool named 'www0'.
[www0]
; pool_id0php_fpm_service_namephp-fpmtemplatepool.conf.erbnamewwwenabletrue
; The address on which to accept FastCGI requests.
; Valid syntaxes are:
; 'ip.add.re.ss:port' - to listen on a TCP socket to a specific address on
; a specific port;
; 'port' - to listen on a TCP socket to all addresses on a
; specific port;
; '/path/to/unix/socket' - to listen on a unix socket.
; Note: This value is mandatory.
listen = 127.0.0.1:9000
; Set listen(2) backlog. A value of '-1' means unlimited.
; Default Value: -1
listen.backlog = 4096
; List of ipv4 addresses of FastCGI clients which are allowed to connect.
; Equivalent to the FCGI_WEB_SERVER_ADDRS environment variable in the original
; PHP FCGI (5.2.2+). Makes sense only with a tcp listening socket. Each address
; must be separated by a comma. If this value is left blank, connections will be
; accepted from any ip address.
; Default Value: any
listen.allowed_clients = 127.0.0.1
; Set permissions for unix socket, if one is used. In Linux, read/write
; permissions must be set in order to allow connections from a web server. Many
; BSD-derived systems allow connections regardless of permissions.
; Default Values: user and group are set as the running user
; mode is set to 0666
;listen.owner = nobody
;listen.group = nobody
;listen.mode = 0666
listen.owner = nginx
listen.group = nginx
listen.mode = 0660
; Unix user/group of processes
; Note: The user is mandatory. If the group is not set, the default user's group
; will be used.
; RPM: apache Choosed to be able to access some dir as httpd
user = nginx
; RPM: Keep a group allowed to write in log dir.
group = nginx
; Choose how the process manager will control the number of child processes.
; Possible Values:
; static - a fixed number (pm.max_children) of child processes;
; dynamic - the number of child processes are set dynamically based on the
; following directives:
; pm.max_children - the maximum number of children that can
; be alive at the same time.
; pm.start_servers - the number of children created on startup.
; pm.min_spare_servers - the minimum number of children in 'idle'
; state (waiting to process). If the number
; of 'idle' processes is less than this
; number then some children will be created.
; pm.max_spare_servers - the maximum number of children in 'idle'
; state (waiting to process). If the number
; of 'idle' processes is greater than this
; number then some children will be killed.
; Note: This value is mandatory.
pm = static
; The number of child processes to be created when pm is set to 'static' and the
; maximum number of child processes to be created when pm is set to 'dynamic'.
; This value sets the limit on the number of simultaneous requests that will be
; served. Equivalent to the ApacheMaxClients directive with mpm_prefork.
; Equivalent to the PHP_FCGI_CHILDREN environment variable in the original PHP
; CGI.
; Note: Used when pm is set to either 'static' or 'dynamic'
; Note: This value is mandatory.
pm.max_children = 48
; The number of requests each child process should execute before respawning.
; This can be useful to work around memory leaks in 3rd party libraries. For
; endless request processing specify '0'. Equivalent to PHP_FCGI_MAX_REQUESTS.
; Default Value: 0
pm.max_requests = 10000
; The URI to view the FPM status page. If this value is not set, no URI will be
; recognized as a status page. By default, the status page shows the following
; information:
; accepted conn - the number of request accepted by the pool;
; pool - the name of the pool;
; process manager - static or dynamic;
; idle processes - the number of idle processes;
; active processes - the number of active processes;
; total processes - the number of idle + active processes.
; The values of 'idle processes', 'active processes' and 'total processes' are
; updated each second. The value of 'accepted conn' is updated in real time.
; Example output:
; accepted conn: 12073
; pool: www
; process manager: static
; idle processes: 35
; active processes: 65
; total processes: 100
; By default the status page output is formatted as text/plain. Passing either
; 'html' or 'json' as a query string will return the corresponding output
; syntax. Example:
; http://www.foo.bar/status
; http://www.foo.bar/status?json
; http://www.foo.bar/status?html
; Note: The value must start with a leading slash (/). The value can be
; anything, but it may not be a good idea to use the .php extension or it
; may conflict with a real PHP file.
; Default Value: not set
;pm.status_path = /status
; The ping URI to call the monitoring page of FPM. If this value is not set, no
; URI will be recognized as a ping page. This could be used to test from outside
; that FPM is alive and responding, or to
; - create a graph of FPM availability (rrd or such);
; - remove a server from a group if it is not responding (load balancing);
; - trigger alerts for the operating team (24/7).
; Note: The value must start with a leading slash (/). The value can be
; anything, but it may not be a good idea to use the .php extension or it
; may conflict with a real PHP file.
; Default Value: not set
;ping.path = /ping
; This directive may be used to customize the response of a ping request. The
; response is formatted as text/plain with a 200 response code.
; Default Value: pong
;ping.response = pong
; The timeout for serving a single request after which the worker process will
; be killed. This option should be used when the 'max_execution_time' ini option
; does not stop script execution for some reason. A value of '0' means 'off'.
; Available units: s(econds)(default), m(inutes), h(ours), or d(ays)
; Default Value: 0
request_terminate_timeout = 60s
; The timeout for serving a single request after which a PHP backtrace will be
; dumped to the 'slowlog' file. A value of '0s' means 'off'.
; Available units: s(econds)(default), m(inutes), h(ours), or d(ays)
; Default Value: 0
request_slowlog_timeout = 20s
; The log file for slow requests
; Default Value: not set
; Note: slowlog is mandatory if request_slowlog_timeout is set
slowlog = /var/log/php-fpm/www-slow.log
; Set open file descriptor rlimit.
; Default Value: system defined value
;rlimit_files = 1024
; Set max core size rlimit.
; Possible Values: 'unlimited' or an integer greater or equal to 0
; Default Value: system defined value
;rlimit_core = 0
; Chroot to this directory at the start. This value must be defined as an
; absolute path. When this value is not set, chroot is not used.
; Note: chrooting is a great security feature and should be used whenever
; possible. However, all PHP paths will be relative to the chroot
; (error_log, sessions.save_path, ...).
; Default Value: not set
;chroot =
; Chdir to this directory at the start. This value must be an absolute path.
; Default Value: current directory or / when chroot
;chdir = /var/www
; Redirect worker stdout and stderr into main error log. If not set, stdout and
; stderr will be redirected to /dev/null according to FastCGI specs.
; Default Value: no
;catch_workers_output = yes
; Limits the extensions of the main script FPM will allow to parse. This can
; prevent configuration mistakes on the web server side. You should only limit
; FPM to .php extensions to prevent malicious users to use other extensions to
; exectute php code.
; Note: set an empty value to allow all extensions.
; Default Value: .php
;security.limit_extensions = .php .php3 .php4 .php5
; Pass environment variables like LD_LIBRARY_PATH. All $VARIABLEs are taken from
; the current environment.
; Default Value: clean env
;env[HOSTNAME] = $HOSTNAME
;env[PATH] = /usr/local/bin:/usr/bin:/bin
;env[TMP] = /tmp
;env[TMPDIR] = /tmp
;env[TEMP] = /tmp
; Additional php.ini defines, specific to this pool of workers. These settings
; overwrite the values previously defined in the php.ini. The directives are the
; same as the PHP SAPI:
; php_value/php_flag - you can set classic ini defines which can
; be overwritten from PHP call 'ini_set'.
; php_admin_value/php_admin_flag - these directives won't be overwritten by
; PHP call 'ini_set'
; For php_*flag, valid values are on, off, 1, 0, true, false, yes or no.
; Defining 'extension' will load the corresponding shared extension from
; extension_dir. Defining 'disable_functions' or 'disable_classes' will not
; overwrite previously defined php.ini values, but will append the new value
; instead.
; Default Value: nothing is defined by default except the values in php.ini and
; specified at startup with the -d argument
;php_admin_value[sendmail_path] = /usr/sbin/sendmail -t -i -f [email protected]
php_flag[display_errors] = off
php_admin_value[error_log] = /var/log/php-fpm/www-error.log
php_admin_flag[log_errors] = on
php_admin_value[memory_limit] = 256M
; Set session path to a directory owned by process user
;php_value[session.save_handler] = files
;php_value[session.save_path] = /var/lib/php/session
答案1
您在 nginx 中为上游 PHP-FPM 使用least_conn负载平衡策略。这意味着，对于一个 IP 地址上的一个用户，可能会由不同的 PHP-FPM 进程提供服务。
如果这两个 PHP-FPM 进程之间不共享有关用户的所有必要状态，那么可能会发生奇怪的事情。例如，如果用户会话状态位于 PHP-FPM 节点本地，那么用户在登录状态下一旦访问另一台服务器就会被注销。
为了避免这种情况，您需要用 替换least_conn。ip_hash这可确保来自一个 IP 地址的所有连接都发送到同一个 PHP-FPM 节点。理论上，这会使负载平衡变得有点不均衡，但实际上没有区别。
但这可能不是您所遇到的问题的原因。
答案2
我认为删除 keepalive 会向您显示潜在的问题，我怀疑这是您配置的超时和后端在负载下的响应程度的组合。
更具体地说，我认为这是你的问题：
upstream php_fpm {
least_conn;
server 127.0.0.1:9000 max_fails=3 fail_timeout=15s;
keepalive 8;
}
我会尝试以下操作：
upstream php_fpm {
least_conn;
server 127.0.0.1:9000 max_fails=3 fail_timeout=60s;
keepalive 8;
}
我认为发生的情况是，PHP-FPM 设置为在 60 秒后终止处理，但 nginx 在 15 秒后认为请求失败。
从https://nginx.org/en/docs/http/ngx_http_upstream_module.html#server：
fail_timeout=time 设定在多长的时间内，尝试与服务器通信失败的次数达到指定次数，服务器才会被视为不可用；在这段时间内，服务器将被视为不可用。默认情况下，该参数设置为 10 秒。
您可能还想检查您的峰值负载是什么样的，并研究扩展您的后端来吸收它。