nginx学习笔记

一个主线程和多个工作进程；

主进程负责读取验证配置文件以及管理维护工作进程；

工作进程采用事件机制高效的负责具体的请求处理，工作进程的数量由配置文件配置或者自适应于服务器的cpu核心数量（worker_process）；

nginx及其模块的工作方式由配置文件决定，通常命名为nginx.conf,路径一般为usr/local/nginx/conf,etc/nginx,user/local/etc/nginx

启动、停止、重启nginx

运行可执行文件可启动nginx，一单启动后可执行带-s参数的命令对nginx进行管理如：

语法：nginx -s params

stop：停止nginx

quit：优雅的停止nginx，工作进程会在完成当前服务的请求后退出；

reload：重新加载配置文件，配置文件改变后不会立即生效，需要运行带该参数的命令后才生效，nginx会加载配置文件，然后验证配置文件并尝试使用新的配置，若成功则启动新的工作进程并发送信号给旧的工作进程让其退出，若不成功则回滚配置。旧的工作进程接受到信号后，会停止接受新的请求，并在服务完当前请求后退出；

reopen：重开日志文件；

管理nginx除了nginx命令外，还可以使用unix系统自带的命令，如kill -s quit pid；

配置文件结构

nginx的模块由配置文件中的指令组成，指令分为简单指令和复杂指令。简单指令由名称和参数构成，其间用空白字符隔开，使用分号结尾。复杂指令与简单指令类似，只是分号换为花括号，花括号内部可以有其他指令，称之为环境上下文。

在所有环境上下文之外的指令称为主环境上下文，如events、http。

在#之后的信息为注释。

http配置

http {

proxy_cache_path filesystem_path key_zone=zoneName:size(k|m) ;

resolver ip valid=time ipv6=[on|off] ;
resolver_timeout time ;

upstream backend {
round_robin(default and it's not a directive) ;
least_conn ;
ip_hash ;
hash [str|variable or combination] ;
least_time ;

# the directive is mandatory for health_checks and on-the-fly reconfiguration of the server group
zone zoneName size(k|m) ;

state /var/lib/nginx/state/upstream_conf_file ;

server domain|host [backup] [weigth=int(default is 1)] [slow_start=count(s)] [max_conns=count] [fail_timeout=30s(10s is assumed)] [max_fails=3(1 is assumed)] [resolve];
...

queue count timeout=int ;

sticky cookie cookie_name [expires=count(s|m|h)] [domain=str] [path=str] ;
sticky route $route_cookie $route_uri ;
sticky learn create= lookup= zone= timeout=
}

match matchName {
status responseCode ;

header str or regex ;
...

body str or regex ;
}

server {
# 代理服务监听的端口
listen host:port default_server(不写 则第一个server为默认的server，当header中的servername匹配不到时，使用默认的server);

proxy_cache zoneName ;
proxy_cache_key $host$request_uri ;
proxy_cache_min_users count ;
proxy_cache_methods GET HEAD POST ;
proxy_cache_valid [responseCode...|any] time(m minutes) ;
proxy_cache_bypass $uri$cookie_nocache ;
proxy_no_cache (defining parameter in the same way as for the proxy_cache_bypass directive) ;

# 当有多个server匹配到一个request时 nginx使用header中的servername
# 可以是全名、可以带星号的通配符、以～开头的正则表达式
# If several names match the Host header, NGINX Plus selects one by searching for names in the following order and using the first match it finds:
# Exact name
# Longest wildcard starting with an asterisk, such as *.example.org
# Longest wildcard ending with an asterisk, such as mail.*
# First matching regular expression (in order of appearance in the configuration file)
server_name [fullname|wildcard|regex] ;

# i don't know what value about this.
root path ;

return responseCode text ;

# Test the URI against all prefix strings.
# The = (equals sign) modifier defines an exact match of the URI and a prefix string. If the exact match is found, the search stops.
# If the ^~ (caret-tilde) modifier prepends the longest matching prefix string, the regular expressions are not checked.
# Store the longest matching prefix string.
# Test the URI against regular expressions.
# Break on the first matching regular expression and use the corresponding location.
# If no regular expression matches, use the location corresponding to the stored prefix string.
location [pathPrefix or regex(should be preceded with ~（case-sensitive） or ～×（case-insensitive）) {
root [local file system path] ;

proxy_pass [porxy http server url(like http://localhost:8080/)] upstreamName;
proxy_set_header headerName headerValue ;
proxy_buffering [on|off] ;
proxy_buffers size number ;
proxy_buffer_size number(k|m) ;
proxy_bind ipAddress ;

health_check interval=count fails=count passes=count match=matchName uri=/path;

gzip [on|off] ;
gzip_types text/html text/plain ... ;
gzip_min_length number (20 is assumed) ;
gzip_proxied no-cache no-store private... ;
gzip_static [on|off] ;
gunzip [on|off] ;

rewrite regex_match regex_replace [last|break] ;

error_page responseCode [error_page_url] ;
error_page 404=301 [new_page_url] ;

fastcgi_pass localhost:9000 ;
fastcgi_param SCRIPT_FILENAME [] ;
fastcgi_param QUERY_STRING    $query_string;

uwsgi_pass uri ;
scgi_pass uri ;
memcached_pass uri ;

open_file_cache_errors [on|off] ;

index [index.htm...] ;

try_files $uri ... last_param ;

sendfile [on|off] ;
sendfile_max_chunk size(1m) ;

tcp_nopush [on|off] ;
tcp_nodelay [on|off] ;

keepalive_timeout number(ms) ;

upstream_conf ;
allow ip ;
deny all|ip ;

return responseCode text ;
}
}
}