Keepalived+Haproxy搭建高可用负载均衡
Keepalived
简单的是一个路由的软件用C写的这个项目的主要目标是提供简单而强大的设施的负载均衡和高可用性对Linux系统和基于Linux的基础设施。负载均衡架构依赖于众所周知的和广泛使用的Linux虚拟服务器（IPVS）内核模块提供第四层负载均衡。简单的实现了一套检测动态自适应维护和管理服务器根据其健康loadbalanced池。另一方面，高可用性的实现VRRP协议.VRRP路由器故障转移的一个基本的砖。此外，简单的实现了一套钩VRRP有限状态机提供低空和高速协议的相互作用。简单的框架可以单独或一起提供弹性基础设施。
Haproxy
HAProxy提供高可用性、负载均衡以及基于TCP和HTTP应用的代理，支持虚拟主机，它是免费、快速并且可靠的一种解决方案。HAProxy特别适用于那些负载特大的web站点，这些站点通常又需要会话保持或七层处理。HAProxy运行在当前的硬件上，完全可以支持数以万计的并发连接。并且它的运行模式使得它可以很简单安全的整合进您当前的架构中， 同时可以保护你的web服务器不被暴露到网络上。
架构图
1、环境
CentOS 6.5 keepalived 1.2.23 haproxy 1.5.4
2、准备4台服务器
VIP 192.168.0.200 Master 192.168.0.110 Backup 192.168.0.111 Server1 192.168.0.120 Server2 192.168.0.121
3、安装gcc编译器，openssl，wget，如果已经安装则跳过
yum -y install openssl-devel ncurses-devel gcc gcc-c++ make rpm-build wget
4、创建软件存放目录
mkdir /soft
5、安装keepalived
cd /soft wget http://www.keepalived.org/software/keepalived-1.2.23.tar.gz tar -zxvf keepalived-1.2.23.tar.gz cd keepalived-1.2.23 ./configure --prefix=/usr/local/keepalived make make install
6、将keepalived做成启动脚务
cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/ cp /usr/local/keepalived/sbin/keepalived /usr/sbin/ cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/ mkdir /etc/keepalived cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/ chmod +x /etc/init.d/keepalived
7、配置文件修改 vim /etc/keepalived/keepalived.conf
7.1、MASTER 配置信息
global_defs {
notification_email
{
fuxiang.gong@qq.com
}
notification_email_from 17091959688@163.com
smtp_server smtp.163.com
stmp_connect_timeout 30
router_id lnmp_node1
}
# 检测haproxy脚本
vrrp_script chk_haproxy {
script "/etc/keepalived/check_haproxy.sh"
interval 2
weight 2
}
# 服务
vrrp_instance VIP_1 {
state MASTER #设置为主服务器
interface eth0 #监测网络接口
virtual_router_id 51 #主、备必须一样
priority 100 #主机级别,值越大优先级越高
advert_int 1 #VRRP Multicast广播周期秒数
authentication {
auth_type PASS #VRRP认证方式，主备必须一致
auth_pass 1111 #密码
}
track_script {
chk_haproxy # 执行监控的服务
}
virtual_ipaddress {
192.168.0.200 #漂移IP地址
}
}
7.2、BACKUP 配置信息
global_defs {
notification_email
{
fuxiang.gong@qq.com
}
notification_email_from 17091959688@163.com
smtp_server smtp.163.com
stmp_connect_timeout 30
router_id lnmp_node2
}
# 检测haproxy脚本
vrrp_script chk_haproxy {
script "/etc/keepalived/check_haproxy.sh"
interval 2
weight 2
}
# 服务
vrrp_instance VIP_1 {
state BACKUP #设置为备用服务器
interface eth0 #监测网络接口
virtual_router_id 51 #主、备必须一样
priority 90 #主、备机取不同的优先级，主机值较大，备份机值较小,值越大优先级越高
advert_int 1 #VRRP Multicast广播周期秒数
authentication {
auth_type PASS #VRRP认证方式，主备必须一致
auth_pass 1111 #密码
}
track_script {
chk_haproxy # 执行监控的服务
}
virtual_ipaddress {
192.168.0.200 #漂移IP地址
}
}
7.3、添加Haproxy检测脚本 vim /etc/keepalived/check_haproxy.sh 添加以下内容
#!/bin/bash if [ $(ps -C haproxy --no-header | wc -l) -eq 0 ]; then /etc/init.d/haproxy start fi sleep 2 if [ $(ps -C haproxy --no-header | wc -l) -eq 0 ]; then /etc/init.d/keepalived stop fi
7.4、给check_haproxy.sh脚本赋值运行权限（MASTER和BACKUP一致）
chmod +x /etc/keepalived/check_haproxy.sh
7.5、允许两台服务器vrrp包通过防火墙，如果关闭防火墙则跳过（两台服务器上都配置）
MASTER vim /etc/sysconfig/iptables -A INPUT -i eth0 -p vrrp -s 192.168.0.111 -j ACCEPT BACKUP vim /etc/sysconfig/iptables -A INPUT -i eth0 -p vrrp -s 192.168.0.110 -j ACCEPT 重启防火墙 service iptables restart
8、启动keepalived服务
service keepalived start
8.1、查看服务器多了一个虚拟IP，keepalived配置成功
MASTER ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:d9:a8:bd brd ff:ff:ff:ff:ff:ff
inet 192.168.0.110/24 brd 192.168.0.255 scope global eth0
inet 192.168.0.200/32 scope global eth0
inet6 fe80::20c:29ff:fed9:a8bd/64 scope link
valid_lft forever preferred_lft forever
BACKUP ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:d9:8f:72 brd ff:ff:ff:ff:ff:ff
inet 192.168.0.109/24 brd 192.168.0.255 scope global eth0
inet6 fe80::20c:29ff:fed9:8f72/64 scope link
valid_lft forever preferred_lft forever
8.2、查看Keepalived日志
tail -f /var/log/messages
9、yum方式安装haproxy
yum install -y haproxy
9.2、查看haproxy版本信息
rpm -qi haproxy 或 haproxy -version Name : haproxy Relocations: (not relocatable) Version : 1.5.4 Vendor: CentOS Release : 3.el6 Build Date: 2016年05月11日 星期三 03时17分37秒 Install Date: 2016年08月24日 星期三 05时34分08秒 Build Host: worker1.bsys.centos.org Group : System Environment/Daemons Source RPM: haproxy-1.5.4-3.el6.src.rpm Size : 2552550 License: GPLv2+ Signature : RSA/SHA1, 2016年05月12日 星期四 18时49分33秒, Key ID 0946fca2c105b9de Packager : CentOS BuildSystem <http://bugs.centos.org> URL : http://www.haproxy.org/ Summary : HAProxy is a TCP/HTTP reverse proxy for high availability environments 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 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, and delete HTTP headers in both directions - block requests matching particular patterns - persists clients to the correct application server depending on application cookies - report detailed status as HTML pages to authenticated users from a URI intercepted from the application
9.2、查看haproxy位置
rpm -ql haproxy
10、添加独立日志 vim /etc/rsyslog.conf 在底部添加以下配置信息
# haproxy # Provides UDP syslog reception $ModLoad imudp $UDPServerRun 514 # 启动udp，启动端口后将作为服务器工作 # # Provides TCP syslog reception $ModLoad imtcp $InputTCPServerRun 514 # 启动tcp监听端口 local2.* /var/log/haproxy.log
10.1、重启日志服务
service rsyslog restart
10.2、vim haproxy.cfg 在global端中需要添加此行
log 127.0.0.1 local2
11、配置防火墙，允许80，1080端口访问，添加以下两行（测试可以直接关闭防火墙）
-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT -A INPUT -m state --state NEW -m tcp -p tcp --dport 1080 -j ACCEPT
11.1、重启防火墙
service iptables restart
15、编辑配置文件 vim /etc/haproxy/haproxy.cfg
15.1、一个最简单的http服务的配置
global log 127.0.0.1 local2 # 定义日志 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon stats socket /var/lib/haproxy/stats defaults mode http log global option httplog option dontlognull option http-server-close option forwardfor except 127.0.0.0/8 option redispatch retries 3 timeout http-request 10s timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout http-keep-alive 10s timeout check 10s maxconn 3000 frontend webser #webser为名称 option forwardfor bind *:80 default_backend webserver backend webserver balance roundrobin #使拥roundrobin 算法 server app1 192.168.1.120:80 check server app2 192.168.1.121:80 check
15.2、haproxy统计页面的输出机制
frontend webser log 127.0.0.1 local2 option forwardfor bind *:80 default_backend webserver backend webserver cookie node insert nocache balance roundrobin server app1 192.168.0.120:80 check cookie node1 intval 2 rise 1 fall 2 server app2 192.168.0.121:80 check cookie node2 intval 2 rise 1 fall 2 listen statistics bind *:8009 # 自定义监听端口 stats enable # 启用基于程序编译时默认设置的统计报告 stats auth admin:admin # 统计页面用户名和密码设置 stats uri /admin?stats # 自定义统计页面的URL，默认为/haproxy?stats stats hide-version # 隐藏统计页面上HAProxy的版本信息 stats refresh 30s # 统计页面自动刷新时间 stats admin if TRUE #如果认证通过就做管理功能，可以管理后端的服务器 stats realm Hapadmin # 统计页面密码框上提示文本，默认为Haproxy\ Statistics
15.3、静态与动态请求分离
# web服务 frontend webservs # 绑定80端口，域名不限 bind *:80 # 定义静态规则 acl url_static path_beg -i /static /images /javascript /stylesheets acl url_static path_end -i .jpg .gif .png .css .js .html acl host_static hdr_beg(host) -i img. imgs. video. videos. ftp. image. download. # 定义动态规则 acl url_php path_end -i .php # 后端请求归纳 use_backend static if url_static or host_static use_backend dynamic if url_php # 默认动态组 default_backend dynamic # 静态请求处理 backend static # 分配算法（轮流分配） balance roundrobin # 实际处理请求的服务器列表 server node1 192.168.0.120:80 check maxconn 3000 # 动态请求处理 backend dynamic # 分配算法（轮流分配） balance roundrobin # 实际处理请求的服务器列表 server node1 192.168.0.121:80 check maxconn 3000 server node2 192.168.0.122:80 check maxconn 3000
15.4、http完整配置负载均衡
#--------------------------------------------------------------------- # Global settings #--------------------------------------------------------------------- global # to have these messages end up in /var/log/haproxy.log you will # need to: # # 1) configure syslog to accept network log events. This is done # by adding the '-r' option to the SYSLOGD_OPTIONS in # /etc/sysconfig/syslog # # 2) configure local2 events to go to the /var/log/haproxy.log # file. A line like the following can be added to # /etc/sysconfig/syslog # # local2.* /var/log/haproxy.log # log 127.0.0.1 local2 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon defaults mode http log global option httplog option dontlognull option http-server-close option forwardfor except 127.0.0.0/8 option redispatch retries 3 timeout http-request 10s timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout http-keep-alive 10s timeout check 10s maxconn 30000 listen stats mode http bind 0.0.0.0:1080 stats enable stats hide-version stats uri /haproxyadmin?stats stats realm Haproxy\ Statistics stats auth admin:admin stats admin if TRUE frontend http-in bind *:80 mode http log global option httpclose option logasap #不等待响应结束就记录日志，表示提前记录日志，一般日志会记录响应时长，此不记录响应时长 option dontlognull #不记录空信息 capture request header Host len 20 #记录请求首部的前20个字符 capture request header Referer len 60 #referer跳转引用，就是上一级 default_backend servers frontend healthcheck bind :1099 #定义外部检测机制 mode http option httpclose option forwardfor default_backend servers backend servers balance roundrobin server websrv1 192.168.0.120:80 check maxconn 2000 server websrv2 192.168.0.121:80 check maxconn 2000
15.5、MySQL完整配置负载均衡
#--------------------------------------------------------------------- # Global settings #--------------------------------------------------------------------- global # to have these messages end up in /var/log/haproxy.log you will # need to: # # 1) configure syslog to accept network log events. This is done # by adding the '-r' option to the SYSLOGD_OPTIONS in # /etc/sysconfig/syslog # # 2) configure local2 events to go to the /var/log/haproxy.log # file. A line like the following can be added to # /etc/sysconfig/syslog # # local2.* /var/log/haproxy.log # log 127.0.0.1 local2 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon defaults mode tcp log global option httplog option dontlognull retries 3 timeout http-request 10s timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout http-keep-alive 10s timeout check 10s maxconn 600 listen stats mode http bind 0.0.0.0:1080 stats enable stats hide-version stats uri /haproxyadmin?stats stats realm Haproxy\ Statistics stats auth admin:admin stats admin if TRUE frontend mysql bind *:3306 mode tcp log global default_backend mysqlservers backend mysqlservers balance leastconn server dbsrv1 192.168.1.120:3306 check port 3306 intval 2 rise 1 fall 2 maxconn 300 server dbsrv2 192.168.1.121:3306 check port 3306 intval 2 rise 1 fall 2 maxconn 300
16、启动haproxy服务
service haproxy start
17、查看统计页面
http://192.168.0.200:1080/haproxyadmin?stats 用户名和密码 admin
18、查看Haproxy日志
tail -f /var/log/haproxy.log
19、Haproxy配置信息 MASTR 与 BACKUP配置完全相同
20、访问服务器VIP地址会自动分配到不同服务器进行处理
http://192.168.0.200 1、关闭MASTER服务，BACKUP会自动升级为MASTER接替服务。启动MASTER的Keepalived服务，会自动切回原来的MASTER服务器。 2、关闭Haproxy服务，脚本会尝试启动Haproxy服务，如果启动失败则关闭Keepalived服务，让备用服务器接替。
到这里一个完整的web负载均衡服务器就配置完成了，Haproxy主要做服务分配，Keepalived做双机热备，Keepalived还可以配置成双主热备。在keepalived中检测Haproxy是否可用，不可用是否关闭Keepalived服务器，具体可以根据自己业务做处理。
