keepalived+haproxy实现web服务的高可用和负载均衡

简介:

keepalived是一个类似于layer3, 4 & 5交换机制的软件,也就是我们平时说的第3层、第4层和第5层交换.Keepalived的作用是检测web服务器的状态,如果有一台web服务器死机,或工作出现故障,Keepalived将检测到,并将有故障的web服务器从系统中剔除,当web服务器工作正常后Keepalived自动将web服务器加入到服务器群中,这些工作全部自动完成,不需要人工干涉,需要人工做的只是修复故障的web服务器.

Haproxy 反向代理服务器,支持双机热备支持虚拟主机,但其配置简单,拥有非常不错的服务器健康检查功能,当其代理的后端服务器出现故障, HAProxy会自动将该服务器摘除,故障恢复后再自动将该服务器加入.新的1.3引入了frontend,backend,frontend根据任意HTTP请求头内容做规则匹配,然后把请求定向到相关的backend.

实验环境以及服务器信息:

OS:   RedHat  AS 5.1

软件列表:

keepalived-1.2.2.tar.gz

haproxy-1.4.13.tar.gz

服务器信息:

Master server  10.10.0.99   (调度主服务器)

Slave server    10.10.0.98   (从调度服务器)

VIP: 10.10.0.97  (调度服务器的虚拟IP)

Real server:

10.10.0.96

10.10.0.95

安装keepalived

#  tar zxvf  keepalived-1.2.2.tar.gz

#  cd keepalived-1.2.2

#  ./configure –-prefix=/usr/local/keepalived

#  make&&make install

#  cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
#  cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
#  mkdir /etc/keepalived
#  cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
#  cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

#  chkconfig –add keepalived

#  chkconfig  keepalived on

#  vi /etc/keepalived/keepalived.conf

global_defs {

notification_email {

xxxxxx@139.com

}

notification_email_from xxxxxx@139.com

smtp_server mail.139.com

smtp_connect_timeout 30

router_id LVS_DEVEL
}

vrrp_instance VI_1 {

state MASTER

interface eth1

virtual_router_id 51

priority 100

advert_int

authentication {

auth_type PASS

auth_pass 1111
}

virtual_ipaddress {

192.168.0.97

}

}

virtual_server 10.10.0.97 80 {

delay_loop 6
lb_algo rr
lb_kind DR
persistence_timeout 50
protocol TCP

real_server 10.10.0.95 80 {
weight 1
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
}
}

real_server 10.10.0.96 80 {
weight 1
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
}
}

}

关于keepalived配置文件的选项解释 可以去网上搜下 由于选项参数居多这里就不说明了

#  service keepalived start

安装haproxy

#   tar zxvf  haproxy-1.4.13.tar.gz

#   mv  haproxy-1.4.13 haproxy

#   cd haproxy

#   make TARGET=linux26

#   vi /usr/local/haproxy/conf/haproxy.conf

#   mkdir –p /var/chroot/haproxy

global
chroot /var/chroot/haproxy
daemon
gid     0
log 127.0.0.1 local3
nbproc  2
pidfile /var/run/haproxy-private.pid
ulimit   -n        65535
user    root
maxconn         32000
spread-checks           4
tune.maxaccept          8
tune.maxpollevents      100
defaults sxit
log     global
mode    http
option  httplog
option  dontlognull
log 127.0.0.1 local3
retries 3
option redispatch
maxconn     32000
contimeout      5000
clitimeout        50000
srvtimeout       50000
listen  sxit 0.0.0.0:80
appsession JSESSIONID len 52 timeout 3h
cookie SRV insert indirect nocache
mode http
stats enable
stats hide-version
stats uri  /haproxy-stats
stats realm Haproxy\ statistics
stats auth sxit:sxit

stats refresh 3s
monitor-uri /haproxy_test
balance roundrobin
option httpclose
option forwardfor
option httpchk HEAD /index.html HTTP/1.0
server s1 10.10.0.98:80 check inter 2000  weight 3
server s3 10.10.0.99:80 check inter 2000  weight 3

# /usr/local/haproxy/sbin/haproxy –f  /usr/local/haproxy/config/haproxy.config

如果启动没有报什么错误的话,就在浏览器上输入如下地址

http://10.10.0.97/haproxy-stats  (查看服务器状态信息的页面,登录的时候输入上面设置的账号和密码sxit),页面状态如下:

wps_clip_image-3309

测试负载均衡效果以及高可用性
负载均衡测试:

启动真实服务器的web服务,在2个真实服务器上创建2个首页文件,内容分别为test1和test2,如果在浏览器上访问web服务每次刷新既显示test1又显示tetst2就说明负载均衡已经生效了.

高可用性测试:

拔掉主调度服务器的网线或者关闭主调度服务器,看下VIP是否顺利的切换到从调度器,假如切换正常,那就说明keepalived已经成功生效了.

发表评论