lvs+keepalived+httpd高可用集群
阿新 • • 發佈：2018-04-01
lvs keepalived httpd實驗環境
（1）本次基於VMware Workstation搭建一個四臺Linux（CentOS 7.4）系統所構成的一個服務器集群，其中兩臺負載均衡服務器（一臺為主機，另一臺為備機），另外兩臺作為真實的Web服務器（向外部提供http服務，這裏僅僅使用了CentOS默認自帶的http服務，沒有安裝其他的類似Tomcat、Jexus服務）。
（2）本次實驗基於DR負載均衡模式，設置了一個VIP（Virtual IP）為172.18.38.99，用戶只需要訪問這個IP地址即可獲得網頁服務。其中，負載均衡主機為172.18.38.100，備機為172.18.38.101。Web服務器A為172.18.38.200，Web服務器B為172.18.38.201。
實驗準備
(1)，綁定靜態IP地址
[root@centos7-100 ~]# nmcli connection modify ens37 ipv4.addresses 172.18.38.100/16 ipv4.method manual connection.autoconnect yes [root@centos7-101 ~]# nmcli connection modify ens37 ipv4.addresses 172.18.38.101/16 ipv4.method manual connection.autoconnect yes [root@centos7-200 ~]# nmcli connection modify ens37 ipv4.addresses 172.18.38.200/16 ipv4.method manual connection.autoconnect yes [root@centos7-201 ~]# nmcli connection modify ens37 ipv4.addresses 172.18.38.201/16 ipv4.method manual connection.autoconnect yes
(2)，同步時間
利用chronyd服務同步時間
1，在四臺主機上都執行下面的命令，註意時間服務器必須是一臺
1，修改配置文件 vim /etc/chrony.conf # Please consider joining the pool (http://www.pool.ntp.org/join.html). server 172.18.0.1 iburst #指定一臺服務器 2，利用下面這條命令概略同步一下 ntpdate 172.18.0.1 1 Apr 13:23:31 ntpdate[8517]: adjust time server 172.18.0.1 offset -0.350642 sec 3，重啟chrony服務 systemctl restart chronyd.service
(3)，關閉防火墻
systemctl disable firewalld
systemctl stop firewalld(3)，LVS+keepalived主從配置
1，在兩臺lvs服務器下載keepalived
yum -y install keepalived1，keepvlived_master+lvs配置文件
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost #出問題了發郵件給誰
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1 #本機郵件服務器
smtp_connect_timeout 30 #超時時間
router_id proxy1 #服務器id
vrrp_mcast_group4 224.1.1.1 #多播地址所有的keepalived會在這個地址通訊，決定誰工作
}
vrrp_instance VI_1 {
state MASTER #主服務器
interface ens37 #網卡接口
virtual_router_id 66 #服務器id
priority 100 #優先級，
advert_int 1 #心跳檢測 1秒一次
authentication { #驗證
auth_type PASS #驗證類型，基於密碼
auth_pass 123456 #密碼
}
virtual_ipaddress {
172.18.38.99/16 #共享IP
}
}
virtual_server 172.18.38.99 80 {
delay_loop 6
lb_algo rr #調度算法
lb_kind DR #調度模型
#persistence_timeout 50
protocol TCP
sorry_server 127.0.0.1 80
real_server 172.18.38.200 80 { #後端server_IP 及端口
weight 1 #權重
HTTP_GET { #健康檢測方式
url {
path /
status_code 200
}
connect_timeout 3 #超時時間
nb_get_retry 3 #重試次數
delay_before_retry 3 #多長時間重試
}
}
real_server 172.18.38.201 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
}
2，keepalived_slave+lvs配置
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id proxy1
vrrp_mcast_group4 224.1.1.1
}
vrrp_instance VI_2 {
state SLAVE "slave關鍵配置"
interface ens37
virtual_router_id 88
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
172.18.38.99/16
}
}
virtual_server 172.18.38.99 80 {
delay_loop 6
lb_algo rr
lb_kind DR
#persistence_timeout 50
protocol TCP
sorry_server 127.0.0.1 80
real_server 172.18.38.200 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
real_server 172.18.38.201 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
}
3，在兩臺lvs服務器下載ipvsadm包
yum install ipvsadm4，在兩臺lvs主機上都啟動keepalived服務
systemctl start keepalived
systemctl enable keepalived5，註意這時候會在ens37網卡上加上一個新的IP
[root@centos7-lvs_master ~]# ip a
ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:50:56:39:48:cc brd ff:ff:ff:ff:ff:ff
inet 172.18.38.101/16 brd 172.18.255.255 scope global ens37
valid_lft forever preferred_lft forever
inet 172.18.38.99/16 scope global secondary ens37
valid_lft forever preferred_lft forever
inet6 fe80::a7b9:b100:4f55:480e/64 scope link
valid_lft forever preferred_lft forever
[root@centos7-lvs_slave ~]# ip a
ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:50:56:39:48:cc brd ff:ff:ff:ff:ff:ff
inet 172.18.38.101/16 brd 172.18.255.255 scope global ens37
valid_lft forever preferred_lft forever
inet 172.18.38.99/16 scope global secondary ens37
valid_lft forever preferred_lft forever
inet6 fe80::a7b9:b100:4f55:480e/64 scope link
valid_lft forever preferred_lft forever
5，查看調度規則
[root@centos7-lvs_master ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 172.18.38.99:80 rr
-> 172.18.38.200:80 Route 1 0 4
-> 172.18.38.201:80 Route 1 0 4
[root@centos7-lvs_slave ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 172.18.38.99:80 rr
-> 172.18.38.200:80 Route 1 0 0
-> 172.18.38.201:80 Route 1 0 0 (4)，配置2個後端web服務器
1，安裝httpd軟件
1，安裝httpd軟件
yum install http
2，啟動服務
systemctl start httpd
systemctl enable httpd
2，生成web頁面，
A主機
echo web_server_A > /var/www/html/index.html
b主機
echo web_server_B > /var/www/html/index.html
2，在兩個web服務器執行下面的腳本，會在lo網卡上生成一個vip
vim lvs_br_rs.sh
#!/bin/bash
#Author:wangxiaochun
#Date:2017-08-13
vip=172.18.38.99 "只需要修改一下IP即可"
mask=‘255.255.255.255‘
dev=lo:1
case $1 in
start)
echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore
echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce
ifconfig $dev $vip netmask $mask #broadcast $vip up
#route add -host $vip dev $dev
echo "The RS Server is Ready!"
;;
stop)
ifconfig $dev down
echo 0 > /proc/sys/net/ipv4/conf/all/arp_ignore
echo 0 > /proc/sys/net/ipv4/conf/lo/arp_ignore
echo 0 > /proc/sys/net/ipv4/conf/all/arp_announce
echo 0 > /proc/sys/net/ipv4/conf/lo/arp_announce
echo "The RS Server is Canceled!"
;;
*)
echo "Usage: $(basename $0) start|stop"
exit 1
;;
esac
3，查看lo網卡
[root@centos7-web_server_A ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet 172.18.38.99/32 scope global lo:1
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
[root@centos7-web_server_B ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet 172.18.38.99/32 scope global lo:1
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever客戶端測試
1，不宕任何服務
[root@centos6 ~]# for i in {1..10};do sleep 0.5;curl 172.18.38.99;done
web_server_B
web_server_A
web_server_B
web_server_A
web_server_B
web_server_A
web_server_B
web_server_A
web_server_B
web_server_A
2，宕掉一臺keepalived測試
[root@centos7 lvs_master ~]# systemctl stop keepalived.service
[root@centos6 ~]# for i in {1..10};do sleep 0.5;curl 172.18.38.99;done
web_server_B
web_server_A
web_server_B
web_server_A
web_server_B
web_server_A
web_server_B
web_server_A
web_server_B
web_server_A
測試通過
lvs+keepalived+httpd高可用集群