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