#yum install gcc gcc-c++ make#groupadd haproxy#useradd haproxy –g haproxy -s /sbin/nologin#wget http://www.haproxy.org/download/1.6/src/haproxy-1.6.4.tar.gz#cd haproxy-1.6.4#make TARGET=linux2628 PREFIX=/usr/local/haproxy#make install PREFIX=/usr/local/haproxy#mkdir -p /etc/haproxy/#cp examples/haproxy.init /etc/init.d/haproxy#chmod +x /etc/init.d/haproxy#ln -s /usr/local/haproxy/sbin/haproxy /usr/sbin/三、软件配置 1.主要配置文件haproxy.cfg
[root@localhost ~]# vi /etc/haproxy/haproxy.cfgglobal log 127.0.0.1 local0 info maxconn 4096 user haproxy group haproxy daemon nbproc 1 chroot /usr/local/haproxy pidfile /var/run/haproxy.piddefaults log global mode tcp option tcplog option dontlognull option redispatch retries 3 maxconn 2000 timeout connect 10s timeout client 60s timeout server 60sfrontend postgres-front bind *:1949 mode tcp default_backend postgresqllisten postgresql mode tcp option tcplog balance leastconn #balance roundrobin #option mysql-check user haproxy #server mysql-1 192.168.184.131:3306 weight 1 check inter 2000 rise 2 fall 3 #server mysql-2 192.168.184.132:3306 weight 1 check inter 2000 rise 2 fall 3 option pgsql-check user haproxy server postgre_1 192.168.184.131:1949 weight 1 check inter 2000 rise 2 fall 3 server postgre_2 192.168.184.132:1949 weight 1 check inter 2000 rise 2 fall 3listen admin-stats mode http option httplog bind 0.0.0.0:8888 stats enable stats refresh 30s stats uri /dbs stats realm welcome login\ Haproxy stats auth admin:admin stats admin if TRUE [root@localhost ~]#2.日志文件
[root@localhost ~]# vi /etc/rsyslog.d/haproxy.conf$ModLoad imudp$UDPServerRun 514local0.* /usr/local/haproxy/haproxy.log[root@localhost ~]# vi /etc/sysconfig/rsyslogSYSLOGD_OPTIONS="-c 2 -r -m 0"[root@localhost ~]# service rsyslog restart四、使用 1.启动关闭
[root@localhost ~]# chkconfig haproxy on[root@localhost ~]# service haproxy start/stop/restart2.验证 打开浏览器,输入 http://192.168.226.148:8888/dbs，用户密码是上面配置的admin/admin 会出来如下页面 ，如果一台pg挂了，则相关node行数据会显示显眼的红色
3.服务端验证 在133和143服务器上各建一个库db_kenyon，创建haproxy的用户，在下面建不同的表来验证 133上建表tbl_1 [postgres@localhost ~]$ psql psql (9.5.2) Type "help" for help. postgres=# create database db_kenyon; CREATE DATABASE postgres=# \c db_kenyon You are now connected to database "db_kenyon" as user "postgres". db_kenyon=# create table tbl_1(id int); CREATE TABLE 同样，143上建表tbl_2 在148上执行验证，148上建postgresql的客户端，并在133和143的pg_hba.conf里设置允许148为trust访问 host all all 192.168.226.148/32 trust [root@localhost ~]# psql -h127.0.0.1 -p13306 -Uhaproxy db_kenyon -c"\dt" List of relations Schema | Name | Type | Owner --------+-------+-------+---------- public | tbl_2 | table | postgres (1 row) [root@localhost ~]# psql -h127.0.0.1 -p13306 -Uhaproxy db_kenyon -c"\dt" List of relations Schema | Name | Type | Owner --------+-------+-------+---------- public | tbl_1 | table | postgres (1 row) 可以看到实现了负载均衡 五、性能简单压测 在两台服务器的db_kenyon库里建同样的表tbl_1，并插入10000条数据 [postgres@localhost ~]$ psql db_kenyonpsql (9.5.2)Type "help" for help.db_kenyon=# select * from tbl_1; id ----(0 rows)db_kenyon=# insert into tbl_1 select generate_series(1,10000);INSERT 0 10000db_kenyon=# \q[postgres@localhost ~]$[postgres@localhost ~]$ more test.conf \set naccounts 10000 * :scale\setrandom id 1 :naccountsSELECT id FROM tbl_1 WHERE id = :id;--单台压测[postgres@localhost ~]$ pgbench -c 25 -j 25 -M prepared -n -s 500 -T 60 db_kenyon -f ./test.conf transaction type: Custom queryscaling factor: 500query mode: preparednumber of clients: 25number of threads: 25duration: 60 snumber of transactions actually processed: 94052latency average: 15.949 mstps = 1619.015406 (including connections establishing)tps = 1622.670100 (excluding connections establishing)--加了haproxy压测[root@localhost ~]# pgbench -c 25 -j 25 -M prepared -n -s 500 -T 60 -h127.0.0.1 -p13306 -Uhaproxy db_kenyon -f ./test.conftransaction type: Custom queryscaling factor: 500query mode: preparednumber of clients: 25number of threads: 25duration: 60 snumber of transactions actually processed: 175073latency average: 8.568 mstps = 2916.996809 (including connections establishing)tps = 2918.372106 (excluding connections establishing)可以看到tps增加了接近一倍，假如slave节点机子越多，该tps会有更大的提高六、关键参数及其他 主要挑几个cfg配置文件里的参数说明： mode tcp ：采用tcp模式 option pgsql-check user haproxy ：haproxy内置的postgres检测模块，后面的haproxy是数据库内用户名 server postgre_1 192.168.184.131:1949 weight 1 check inter 2000 rise 2 fall 3 :设置访问节点服务，每2秒检测超过3次失败则失败，从失败转成成功则需要检测2次，weight是分配权重。同样的模块还有mysql-check balance leastconn ：这个算法是最少连接数，还有个注释掉的roundrobin是轮训的方式
系统可以考虑加上keepalived和pgbouncer来搭整套环境，haproxy除了可以做负载均衡，还可以用来做读的ha和简单的状态监控，可以有效降低单台服务器的负载，单台压测cpu基本饱和，加了haproxy后每台cpu还能空出20%出来。
七、参考http://www.haproxy.com/