haproxy使用总结
DESCRIPTION
?????? HAProxy is a TCP/HTTP reverse proxy which is particularly suited for high availability environments.? Indeed,? it
?????? can:
??????? - route HTTP requests depending on statically assigned cookies ;
??????? - spread the load among several servers while assuring server
????????? persistence through the use of HTTP cookies ;
??????? - switch to backup servers in the event a main one fails ;
??????? - accept connections to special ports dedicated to service
????????? monitoring ;
??????? - stop accepting connections without breaking existing ones ;
??????? - add/modify/delete HTTP headers both ways ;
??????? - block requests matching a particular pattern ;
??????? - hold clients to the right application server depending on
????????? application cookies
??????? - report detailed status as HTML pages to authenticated users from an
????????? URI intercepted from the application.
?????? It needs very little resource. Its event-driven architecture allows it to easily handle thousands of simultaneous
?????? connections on hundreds of instances without risking the system's stability.
global daemon maxconn 256 defaults mode tcp timeout connect 5000ms timeout client 50000ms timeout server 50000ms frontend testhost bind *:1998 default_backend servers backend servers server server52 127.0.0.1:52 check server server872 127.0.0.1:872 check server server42 127.0.0.1:42 check retries 3 redispatch?灾难备份
global daemon maxconn 256 log 127.0.0.1 local3 pidfile /tmp/haproxy.pid #stats socket /tmp/haproxy_1.5_dev_11.stats.socket defaults mode tcp timeout connect 5000ms timeout client 50000ms timeout server 50000ms log 127.0.0.1 local3 option log-health-checks frontend testhost bind *:1998 default_backend servers backend servers server server52 127.0.0.1:52 check server server872 127.0.0.1:872 check backup?热启动(修改config让程序立即生效）
#!/bin/bash#haproxy_hot_reload_config.sh#the program will restart the haproxy by using its hot reconfigurationconfig=" /home/prj/haproxy_conf/haproxy.cfg.mysql212"pidfile=`grep pidfile $config | awk '{print $2}'`pid=`cat $pidfile`status=-2if [ -e /proc/$pid/exe ]; then /usr/local/sbin/haproxy -D -f $config -sf $pid status=0else /usr/local/sbin/haproxy -D -f $config status=1fiecho $statusexit $status??