爲了達到高可用目的,一個應用一般會部署多個實例,前面用nginx做負載。有些時候我們希望一個用戶的所有請求都打到其中一個實例上(比如會話或者狀態不能在服務集羣所有實例間進行共享時),nginx官方默認的解決方案是通過ip_hash實現,但是ip hash 不夠準確,ip hash其實就是把客戶端ip v4地址4段中的前3段拿來做hash運算得到一個hash值,通過該hash值決定請求打到哪個服務上;在很多內外應用中,內網用戶很多都在一個網段下,導致ip地址的前3段基本都一樣的,這導致所有請求都會打到其中一個服務實例上,而其他服務實例沒有負載。
sticky負載模式是通過分配的路由碼實現客戶端和後端服務實例綁定。具體處理過程爲:客戶端第一次向服務發起請求時不帶路由碼,nginx通過輪休的負載方式把請求打到其中的一個後端服務實例,確定具體服務實例後,nginx分配一個路由碼帶到響應cookies裏,客戶端在cookies中保存該路由碼,每次請求的時候都帶上,nginx接收到請求後,解析請求頭裏面的route cookies值,根據該值把請求轉發到該值綁定的後端服務實例,達到回話粘粘的效果。
sticky負載模式必須要客戶端支持cookies。
重新編譯nginx
安裝基礎依賴包,下載sticky模塊和nginx源碼和其他模塊。
# yum -y install wget tar git gcc make pcre pcre-devel zlib zlib-devel openssl openssl-devel GeoIP GeoIP-devel#
# cd /tmp
# git clone https://github.com/gnosek/nginx-upstream-fair.git
# git clone https://bitbucket.org/nginx-goodies/nginx-sticky-module-ng.git
# git clone https://github.com/yaoweibin/nginx_upstream_check_module.git
# wget http://nginx.org/download/nginx-1.16.1.tar.gz
解壓編譯
# tar -xvzf nginx-1.16.1.tar.gz
# cd nginx-1.16.1
# ./configure --prefix=/usr/share/nginx --sbin-path=/usr/sbin/nginx --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --http-client-body-temp-path=/var/lib/nginx/tmp/client_body --http-proxy-temp-path=/var/lib/nginx/tmp/proxy --http-fastcgi-temp-path=/var/lib/nginx/tmp/fastcgi --pid-path=/var/run/nginx.pid --lock-path=/var/lock/subsys/nginx --user=nginx --group=nginx --with-http_gzip_static_module --with-http_stub_status_module --with-http_ssl_module --with-pcre --with-file-aio --with-http_realip_module --without-http_scgi_module --without-http_uwsgi_module --without-http_fastcgi_module --with-http_geoip_module --add-module=/tmp/nginx-sticky-module-ng --add-module=/tmp/nginx_upstream_check_module
# make
# make install
# openssl dhparam -out /etc/nginx/dhparams.pem 2048
執行下面的命令,創建需要的目錄和權限
# mkdir /etc/nginx/conf.d
# mkdir -p /var/lib/nginx/tmp/client_body
# chown -R nginx.nginx /var/lib/nginx/
# chmod -R 770 /var/lib/nginx/
創建初始化腳本
添加配置文件/etc/init.d/nginx
讓nginx隨系統啓動一起啓動。
當我們執行service nginx
命令的時候,這個文件將會被執行。
# chmod +x /etc/init.d/nginx
#!/bin/sh
#
# nginx - this script starts and stops the nginx daemin
#
# chkconfig: - 85 15
# description: Nginx is an HTTP(S) server, HTTP(S) reverse \
# proxy and IMAP/POP3 proxy server
# processname: nginx
# config: /etc/nginx/nginx.conf
# pidfile: /var/run/nginx.pid
# user: nginx
# Source function library.
. /etc/rc.d/init.d/functions
# Source networking configuration.
. /etc/sysconfig/network
# Check that networking is up.
[ "$NETWORKING" = "no" ] && exit 0
nginx="/usr/sbin/nginx"
prog=$(basename $nginx)
NGINX_CONF_FILE="/etc/nginx/nginx.conf"
lockfile=/var/run/nginx.lock
start() {
[ -x $nginx ] || exit 5
[ -f $NGINX_CONF_FILE ] || exit 6
echo -n $"Starting $prog: "
daemon $nginx -c $NGINX_CONF_FILE
retval=$?
echo
[ $retval -eq 0 ] && touch $lockfile
return $retval
}
stop() {
echo -n $"Stopping $prog: "
killproc $prog -QUIT
retval=$?
echo
[ $retval -eq 0 ] && rm -f $lockfile
return $retval
}
restart() {
configtest || return $?
stop
start
}
reload() {
configtest || return $?
echo -n $"Reloading $prog: "
killproc $nginx -HUP
RETVAL=$?
echo
}
force_reload() {
restart
}
configtest() {
$nginx -t -c $NGINX_CONF_FILE
}
rh_status() {
status $prog
}
rh_status_q() {
rh_status >/dev/null 2>&1
}
case "$1" in
start)
rh_status_q && exit 0
$1
;;
stop)
rh_status_q || exit 0
$1
;;
restart|configtest)
$1
;;
reload)
rh_status_q || exit 7
$1
;;
force-reload)
force_reload
;;
status)
rh_status
;;
condrestart|try-restart)
rh_status_q || exit 0
;;
*)
echo $"Usage: $0 {start|stop|status|restart|condrestart|try-restart|reload|force-reload|configtest}"
exit 2
esac
讓服務隨系統啓動
# chkconfig --add nginx
# chkconfig --level 345 nginx on
重啓服務
# service nginx restart
檢查編譯模塊
# nginx -V
輸出
nginx version: nginx/1.16.1
built by gcc 4.8.5 20150623 (Red Hat 4.8.5-39) (GCC)
built with OpenSSL 1.0.2k-fips 26 Jan 2017
TLS SNI support enabled
configure arguments: --prefix=/usr/share/nginx --sbin-path=/usr/sbin/nginx --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --http-client-body-temp-path=/var/lib/nginx/tmp/client_body --http-proxy-temp-path=/var/lib/nginx/tmp/proxy --http-fastcgi-temp-path=/var/lib/nginx/tmp/fastcgi --pid-path=/var/run/nginx.pid --lock-path=/var/lock/subsys/nginx --user=nginx --group=nginx --with-http_gzip_static_module --with-http_stub_status_module --with-http_ssl_module --with-pcre --with-file-aio --with-http_realip_module --without-http_scgi_module --without-http_uwsgi_module --without-http_fastcgi_module --with-http_geoip_module --add-module=/tmp/nginx-sticky-module-ng --add-module=/tmp/nginx_upstream_check_module
使用
在/etc/nginx/conf.d
下新建配置文件sticky_test.conf
,upstream負載模式設置爲sticky
,配置內容如下。
upstream sticky.itclj.lo {
sticky;
server 127.0.0.1:8180;
server 127.0.0.1:8280;
}
server {
listen 80;
server_name sticky.itclj.com;
location ~*^.+$ {
proxy_pass http://sticky.itclj.lo;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
}
}
- nginx下負載多個Tomcat請參考:https://blog.csdn.net/clj198606061111/article/details/22621003
- sticky官方完整配置說明:http://nginx.org/en/docs/http/ngx_http_upstream_module.html#sticky