Linux集群架构（二）

2023-07-17 15:55:46

Linux集群架构（二）

八、LVS DR模式搭建

九、keepalived + LVS

十、扩展

八、LVS DR模式搭建

1、实验环境：

四台机器：

client: 10.0.1.50

Director节点： (ens32 10.0.1.55 vip ens32:0 10.0.1.58)

Real server1： (ens32 10.0.1.56 vip lo:0 10.0.1.58)

Real server2： (ens32 10.0.1.57 vip lo:0 10.0.1.58)

2、安装

//两台real server需安装web服务。之前已经装过，略过

//在director安装ipvsadm软件包，可参考lvs nat部分

[root@lvs-dr ~]# yum -y install ipvsadm

3、在director上配置脚本

[root@lvs-dr1 ~]# vim /usr/local/sbin/lvs-dr.sh

#!/bin/bash

echo 1 > /proc/sys/net/ipv4/ip_forward

ipv=/usr/sbin/ipvsadm

vip=10.0.1.58

rs1=10.0.1.56

rs2=10.0.1.57

ifconfig ens32:0 $vip broadcast $vip netmask 255.255.255.255 up

route add -host $vip dev ens32:0

$ipv -C

$ipv -A -t $vip:80 -s rr

$ipv -a -t $vip:80 -r $rs1:80 -g -w 3

$ipv -a -t $vip:80 -r $rs2:80 -g -w 1

//赋予755权限，

[root@lvs-dr1 ~]# chmod 755 /usr/local/sbin/lvs-dr.sh

//执行脚本

[root@lvs-dr1 ~]# /usr/local/sbin/lvs-dr.sh

//查看状态

[root@lvs-dr1 ~]# chmod 755 /usr/local/sbin/lvs-dr.sh^C

[root@lvs-dr1 ~]# ipvsadm -L -n

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  10.0.1.58:80 rr

  -> 10.0.1.56:80                 Route   3      0          0

  -> 10.0.1.57:80                 Route   1      0          0

4、在两台real server配置脚本

[root@lvs-backend1 ~]# vim /usr/local/sbin/lvs-dr-rs.sh

#!/bin/bash

vip=10.0.1.58

ifconfig lo:0 $vip broadcast $vip netmask 255.255.255.255 up

route add -host $vip lo:0

echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore

echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce

echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore

echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce

//赋予755权限，然后执行

[root@lvs-backend1 ~]# chmod 755 /usr/local/sbin/lvs-dr-rs.sh  

//执行

[root@lvs-backend1 ~]# /usr/local/sbin/lvs-dr-rs.sh

5、测试

//当前采用的是rr调度算法

Last login: Mon Jul 23 14:47:55 2018

[root@localhost ~]# ip addr

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

    inet6 ::1/128 scope host

       valid_lft forever preferred_lft forever

2: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

    link/ether 00:0c:29:a2:07:b1 brd ff:ff:ff:ff:ff:ff

    inet 10.0.1.50/24 brd 10.0.1.255 scope global ens32

       valid_lft forever preferred_lft forever

    inet6 fe80::20c:29ff:fea2:7b1/64 scope link

       valid_lft forever preferred_lft forever

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]#

九、keepalived + LVS

LVS可以实现负载均衡，但是不能够进行健康检查，如一个rs出现故障，LVS 仍然会把请求转发给故障的rs服务器，这就会导致请求的无效性。keepalive 软件可以进行健康检查，而且能同时实现 LVS 的高可用性，解决 LVS 单点故障的问题，其实 keepalive 就是为 LVS 而生的。

1、实验环境

4台节点

Keepalived1 + lvs1(Director1)：10.0.1.55

Keepalived2 + lvs2(Director2)：10.0.1.59

Real server1：10.0.1.56

Real server2：10.0.1.57

VIP: 192.168.0.58

2.软件安装

//Keepalived + lvs两个节点安装

[root@localhost ~]# yum install ipvsadm keepalived -y

//两个read server安装nignx, 之前环境已经安装过，此处略

3.设置配置脚本

//两台real server节点建立脚本

[root@lvs-backend1 ~]# vim /usr/local/sbin/lvs-dr-rs.sh

#!/bin/bash

vip=10.0.1.58

ifconfig lo:0 $vip broadcast $vip netmask 255.255.255.255 up

route add -host $vip lo:0

echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore

echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce

echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore

echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce

//赋予755权限，然后执行

[root@lvs-backend1 ~]# chmod 755 /usr/local/sbin/lvs-dr-rs.sh  

//执行

[root@lvs-backend1 ~]# /usr/local/sbin/lvs-dr-rs.sh

//两台keepalived节点配置

//master节点配置文件

[root@lvs-dr1 ~]# vim /etc/keepalived/keepalived.conf

vrrp_instance VI_1 {

    #备用服务器上为 BACKUP

    state MASTER

    interface ens32

    virtual_router_id 51

    #备用服务器上为90

    priority 100

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass aminglinux

    }

    virtual_ipaddress {

        10.0.1.58

    }

}

virtual_server 10.0.1.58 80 {

    #(每隔10秒查询realserver状态)

    delay_loop 10

    #(lvs 算法)

    lb_algo wrr

    #(DR模式)

    lb_kind DR

    #(同一IP的连接60秒内被分配到同一台realserver)

    #实验环境注释掉，不然看不到rr的效果

    #persistence_timeout 60

    #(用TCP协议检查realserver状态)

    protocol TCP

    real_server 10.0.1.56 80 {

        #(权重)

        weight 1

        TCP_CHECK {

        #(10秒无响应超时)

        connect_timeout 10

        nb_get_retry 3

        delay_before_retry 3

        connect_port 80

        }

    }

    real_server 10.0.1.57 80 {

        weight 1

        TCP_CHECK {

        connect_timeout 10

        nb_get_retry 3

        delay_before_retry 3

        connect_port 80

        }

     }

}

//backup节点

[root@lvs-backend2 ~]# vim /etc/keepalived/keepalived.conf

vrrp_instance VI_1 {

    #备用服务器上为 BACKUP

    state BACKUP

    interface ens32

    virtual_router_id 51

    priority 90

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass aminglinux

    }

    virtual_ipaddress {

        10.0.1.58

    }

}

virtual_server 10.0.1.58 80 {

    #(每隔10秒查询realserver状态)

    delay_loop 10

    #(lvs 算法)

    lb_algo rr

    #(DR模式)

    lb_kind DR

    #(同一IP的连接60秒内被分配到同一台realserver)

    #persistence_timeout 60

    #(用TCP协议检查realserver状态)

    protocol TCP

    real_server 10.0.1.56 80 {

        #(权重)

        weight 1

        TCP_CHECK {

        #(10秒无响应超时)

        connect_timeout 10

        nb_get_retry 3

        delay_before_retry 3

        connect_port 80

        }

    }

    real_server 10.0.1.57 80 {

        weight 1

        TCP_CHECK {

        connect_timeout 10

        nb_get_retry 3

        delay_before_retry 3

        connect_port 80

        }

     }

}

4.在keepalived两个节点开启转发功能

[root@lvs-dr1 ~]# echo 1 > /proc/sys/net/ipv4/ip_forward

5.在两个节点启动keepalive,

[root@lvs-dr1 ~]# systemctl start keepalived.service

[root@lvs-dr2 ~]# systemctl start keepalived.service

6.测试

//测试1：手动关闭10.0.1.56节点的nginx，在客户端上去测试访问

//在10.0.1.56上操作

[root@lvs-backend1 ~]# /usr/local/nginx/sbin/nginx -s stop

[root@lvs-backend1 ~]# lsof -i :80

//在10.0.1.50客户端上测试

Last login: Mon Jul 23 14:49:10 2018 from 10.0.1.229

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

//结果正常，不会出现访问10.0.1.56节点，一直访问的是10.0.1.57节点的内容。

//测试2 手动重新开启 10.0.1.56 节点的nginx， 在客户端上去测试访问

//在10.0.1.56上操作

[root@lvs-backend1 ~]# lsof -i :80

[root@lvs-backend1 ~]# /usr/local/nginx/sbin/nginx

[root@lvs-backend1 ~]# lsof -i :80

COMMAND  PID  USER   FD   TYPE DEVICE SIZE/OFF NODE NAME

nginx   2969  root    6u  IPv4  48805      0t0  TCP *:http (LISTEN)

nginx   2970 nginx    6u  IPv4  48805      0t0  TCP *:http (LISTEN)

nginx   2971 nginx    6u  IPv4  48805      0t0  TCP *:http (LISTEN)

//在10.0.1.50上测试

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

//结果正常，按照 rr 调度算法访问10.0.1.56节点和10.0.1.57节点内容。

//测试 keepalived 的HA特性

//ip addr查看，此时10.0.1.58的vip在主上

       valid_lft forever preferred_lft forever

[root@lvs-dr1 ~]# ip addr

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

    inet6 ::1/128 scope host

       valid_lft forever preferred_lft forever

2: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

    link/ether 00:0c:29:85:24:8c brd ff:ff:ff:ff:ff:ff

    inet 10.0.1.55/24 brd 10.0.1.255 scope global ens32

       valid_lft forever preferred_lft forever

    inet 10.0.1.58/32 scope global ens32

       valid_lft forever preferred_lft forever

    inet6 fe80::20c:29ff:fe85:248c/64 scope link

       valid_lft forever preferred_lft forever

//停止master上的keepalived

[root@lvs-dr1 ~]# systemctl stop keepalived.service

[root@lvs-dr1 ~]# 

//在dr2上查看，vip抢占过来了

[root@lvs-dr2 ~]# ip addr

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

    inet6 ::1/128 scope host

       valid_lft forever preferred_lft forever

2: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

    link/ether 00:0c:29:dd:53:4e brd ff:ff:ff:ff:ff:ff

    inet 10.0.1.59/24 brd 10.0.1.255 scope global ens32

       valid_lft forever preferred_lft forever

    inet 10.0.1.58/32 scope global ens32

       valid_lft forever preferred_lft forever

    inet6 fe80::c388:e67a:4ac3:6566/64 scope link

       valid_lft forever preferred_lft forever

//在10.0.1.50上测试

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

I am Lvs-backend1!!!

[root@localhost ~]# curl 10.0.1.58

I am lvs-backend2!!!

[root@localhost ~]# curl 10.0.1.58

//可以正常访问后端的网站,验证了keepalived的特性

//重新开启master上的keepalived

[root@lvs-dr1 ~]# systemctl start keepalived.service

[root@lvs-dr1 ~]# ip add

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

    inet6 ::1/128 scope host

       valid_lft forever preferred_lft forever

2: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

    link/ether 00:0c:29:85:24:8c brd ff:ff:ff:ff:ff:ff

    inet 10.0.1.55/24 brd 10.0.1.255 scope global ens32

       valid_lft forever preferred_lft forever

    inet 10.0.1.58/32 scope global ens32

       valid_lft forever preferred_lft forever

    inet6 fe80::20c:29ff:fe85:248c/64 scope link

       valid_lft forever preferred_lft forever