keepalived + LVS-NAT 双主互备模型

    实验环境拓扑图:

    备注:内网段使用192.168.91.0/24 网段模拟。外网使用192.168.23.0/24网段模拟


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1、两节点上关闭防火墙和selinux。

[root@node1 keepalived]# systemctl stop firewalld  #关闭防火墙

[root@node1 keepalived]# systemctl disable firewalld #关闭防火墙自动启动

#如果不想关闭防火墙就需要开放组播地址224.0.0.18.两个节点之间的是通过这个组播地址发送VRRP相关信息,主要是节点心跳、优先级等信息

[root@node1 keepalived]# systemctl list-unit-files | grep firewalld  #验证是否关闭自动启动。disabled为关闭

firewalld.service                           disabled

#关闭selinux。这个不关闭有可能无法启动keepalived的服务,目前还没有找到解决方案

[root@node1 keepalived]# setenforce 0  # 临时关闭

[root@node1 keepalived]# vim /etc/selinux/config  #永久关闭。disabled为关闭。需要重启系统才能生效

SELINUX=disabled

2、两节点上的时间必须同步。

centos 7 上使用chrony 这个软件实现时间同步,和ntp 类似,据说功能比ntp强大。安装上这个软件即可实现同步,不需要进行额外的配置。

[root@node1 keepalived]# yum -y install chrony  #两个节点上都安装上如果不能上互联网需要配置/etc/chrony.conf,将NTP服务器域名或IP地址加入此文件中

[root@node1 keepalived]# vim /etc/chrony.conf

不能上互联网需要将这四行注释,其实不注释也是可以的,只要将内网NTP服务器加到第一条即可

server ntp.centos7.cn #NTP 服务器的域名:ntp.centos7.cn 可以解析此域名

#server 0.centos.pool.ntp.org iburst

#server 1.centos.pool.ntp.org iburst

#server 2.centos.pool.ntp.org iburst

#server 3.centos.pool.ntp.org iburst

[root@node1 keepalived]# date;ssh node2 'date'

Thu Mar  3 17:55:31 CST 2016

Thu Mar  3 17:55:32 CST 2016

3、两节点之间ssh通过使用密钥访问

#生成公/私钥对。

[root@node1 keepalived]# ssh-keygen #敲两下回车。公/似钥存储的目录/root/.ssh/

#将node1 生成的公钥信息传递到node2 /root/.ssh/目录

[root@node1 .ssh]# cp id_rsa.pub root@node2:/root/.ssh/id_rsa.pub 

#在node2 上将node1 的公钥导入到authorized_keys文件里。原/root/.ssh/目录下没有这个文件就会新建这个文件,有的话就会继续向里面附加内容

[root@node2 .ssh]# cat id_rsa.pub >>authorized_keys

在node2 节点上删除node1 的公钥

[root@node1 .ssh]# rm -f id_rsa.pub

node2 也需要生成公/私钥对,将复制到node1 /root/.ssh/目录下,并将其导入authorized_keys,然后删除node2 的公钥文件

4、两个节点上配置host文件,让两个节点能通过主机名进行通讯.编辑/etc/hosts文件。加如下内容:

192.168.91.129  centos7.cn      node1

192.168.91.130  centos7.cn      node2

5、两个节点上开启路由转发功能

vim /etc/sysctl.conf

net.ipv4.ip_forward=1

[root@node1 ~]# sysctl -p

net.ipv4.ip_forward = 1

确认路由转发功能是否开启。1为开启

[root@node1 keepalived]# cat /proc/sys/net/ipv4/ip_forward

1

6、在两个节点上安装keepalived 和ipvsadm(这个不是必须的,安装了便于查看LVS的相关信息)

yum -y install keepalived ipvsadm;ssh node2 'yum -y install keepalived ipvsadm'

node1 节点上keepalived.conf 配置文件

global_defs 

{

   notification_email 

   {

    root@localhost

   }

   notification_email_from Alexandre.Cassen@firewall.loc

   smtp_server 127.0.0.1

   smtp_connect_timeout 30

   router_id LVS_MASTER

}  

vrrp_instance VI_1 

{

    state MASTER

    interface eno16777736

    virtual_router_id 51

    priority 100

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass abbac1e595fe

    }

    virtual_ipaddress 

    {

        192.168.91.15/32 dev eno16777736 label eno16777736:0

    }

    virtual_routes 

    {

192.168.91.15/32 dev eno16777736:0

    }

}

vrrp_instance VI_2 

{

    state BACKUP

    interface eno16777736

    virtual_router_id 52

    priority 99

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass 1e67cca200cf

    }

    virtual_ipaddress 

    {

        192.168.91.16/32 dev eno16777736 label eno16777736:1

    }

    virtual_routes 

    {

192.168.91.16/32 dev eno16777736:1

    }

}

vrrp_instance VI_3 

{

    state MASTER

    interface eno33554984

    virtual_router_id 53

    priority 100

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass e027a03bcd81

    }

    virtual_ipaddress 

    {

        192.168.23.15/32 dev eno33554984 label eno33554984:0

    }

    virtual_routes 

    {

192.168.23.15/32 dev eno33554984:0

    }

}

vrrp_instance VI_4 

{

    state BACKUP

    interface eno33554984

    virtual_router_id 54

    priority 99

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass f03c1c91c7fc

    }

    virtual_ipaddress 

    {

        192.168.23.14/32 dev eno33554984 label eno33554984:1

    }

    virtual_routes 

    {

192.168.23.14/32 dev eno33554984:1

    }

}

virtual_server 192.168.91.15 80 

{

    delay_loop 6

    lb_algo wrr

    lb_kind NAT

    protocol TCP

    real_server 192.168.23.16 80 

    {

        weight 6

        HTTP_GET 

    {

            url 

  {

              path /

status_code 200

        }

        connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

    real_server 192.168.23.18 80 

    {

        weight 3

        HTTP_GET 

{

           url 

      {

                  path /

    status_code 200

      }

        connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

}

virtual_server 192.168.91.16 80 

{

    delay_loop 6

    lb_algo wrr

    lb_kind NAT

    protocol TCP

    real_server 192.168.23.19 80 

    {

        weight 6

        HTTP_GET 

    {

          url 

      {

                  path /

  status_code 200

       }

        connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

    real_server 192.168.23.17 80 

    {

        weight 3

        HTTP_GET 

{

          url 

{

                  path /

    status_code 200

                }

       connect_timeout 3

       nb_get_retry 3

       delay_before_retry 3

       }

    }

}

[root@node1 keepalived]# systemctl start keepalived  #启动keepalived服务

[root@node1 keepalived]# systemctl enable keepalived # 开机自动启动keepalived服务

Created symlink from /etc/systemd/system/multi-user.target.wants/keepalived.service to /usr/lib/systemd/system/keepalived.service.

[root@node1 keepalived]# systemctl list-unit-files | grep keepalived     #验证开机是否自动启动keepalived服务

keepalived.service                          enabled  

node1 ipvs相关信息

[root@node1 ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  192.168.91.15:80 wrr

  -> 192.168.23.16:80             Masq    6      0          0         

  -> 192.168.23.18:80             Masq    3      0          0         

TCP  192.168.91.16:80 wrr

  -> 192.168.23.19:80             Masq    6      0          0         

  -> 192.168.23.17:80             Masq    3      0          0         

node1 IP地址信息

[root@node1 keepalived]# ifconfig

eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.91.129  netmask 255.255.255.0  broadcast 192.168.91.255

        inet6 fe80::20c:29ff:fec1:fe33  prefixlen 64  scopeid 0x20<link>

        ether 00:0c:29:c1:fe:33  txqueuelen 1000  (Ethernet)

        RX packets 31637  bytes 5942061 (5.6 MiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 30175  bytes 2627032 (2.5 MiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno16777736:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.91.15  netmask 255.255.255.255  broadcast 0.0.0.0

        ether 00:0c:29:c1:fe:33  txqueuelen 1000  (Ethernet)

eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.23.11  netmask 255.255.255.0  broadcast 192.168.23.255

        inet6 fe80::20c:29ff:fec1:fe3d  prefixlen 64  scopeid 0x20<link>

        ether 00:0c:29:c1:fe:3d  txqueuelen 1000  (Ethernet)

        RX packets 63347  bytes 8511811 (8.1 MiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 81785  bytes 6504879 (6.2 MiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno33554984:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.23.15  netmask 255.255.255.255  broadcast 0.0.0.0

        ether 00:0c:29:c1:fe:3d  txqueuelen 1000  (Ethernet)

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536

        inet 127.0.0.1  netmask 255.0.0.0

        inet6 ::1  prefixlen 128  scopeid 0x10<host>

        loop  txqueuelen 0  (Local Loopback)

        RX packets 146  bytes 10759 (10.5 KiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 146  bytes 10759 (10.5 KiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

node2 节点上keepalived.conf 配置文件

global_defs 

{

   notification_email 

   {

    root@localhost

   }

   notification_email_from Alexandre.Cassen@firewall.loc

   smtp_server 127.0.0.1

   smtp_connect_timeout 30

   router_id LVS_BACKUP

}  

vrrp_instance VI_1 {

    state BACKUP

    interface eno16777736

    virtual_router_id 51

    priority 99

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass abbac1e595fe

    }

    virtual_ipaddress 

    {

        192.168.91.15/32 dev eno16777736 label eno16777736:0

    }

    virtual_routes 

    {

192.168.91.15/32 dev eno16777736:0

    }

}

vrrp_instance VI_2 

{

    state MASTER

    interface eno16777736

    virtual_router_id 52

    priority 100

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass 1e67cca200cf

    }

    virtual_ipaddress 

    {

        192.168.91.16/32 dev eno16777736 label eno16777736:1

    }

    virtual_routes 

    {

192.168.91.16/32 dev eno16777736:1

    }

}

vrrp_instance VI_3 {

    state BACKUP

    interface eno33554984

    virtual_router_id 53

    priority 99

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass e027a03bcd81

    }

    virtual_ipaddress

    {

        192.168.23.15/32 dev eno33554984 label eno33554984:0

    }

    virtual_routes 

    {

192.168.23.15/32 dev eno33554984:0

    }

}

vrrp_instance VI_4 

{

    state MASTER

    interface eno33554984

    virtual_router_id 54

    priority 100

    advert_int 1

    authentication 

    {

        auth_type PASS

        auth_pass f03c1c91c7fc

    }

    virtual_ipaddress 

    {

        192.168.23.14/32 dev eno33554984 label eno33554984:1

    }

    virtual_routes 

    {

192.168.23.14/32 dev eno33554984:1

    }

}

virtual_server 192.168.91.15 80 

{

    delay_loop 6

    lb_algo wrr

    lb_kind NAT

    protocol TCP

    real_server 192.168.23.16 80 

    {

        weight 6

        HTTP_GET 

    {

          url 

      {

                path /

    status_code 200

            }

        connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

    real_server 192.168.23.18 80 

    {

        weight 3

        HTTP_GET 

{

            url 

{

              path /

    status_code 200

            }

      connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

}

virtual_server 192.168.91.16 80 

{

    delay_loop 6

    lb_algo wrr

    lb_kind NAT

    protocol TCP

    real_server 192.168.23.19 80 

    {

        weight 6

        HTTP_GET 

       {

          url 

      {

                   path /

   status_code 200

            }

        connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

    real_server 192.168.23.17 80 

    {

        weight 3

        HTTP_GET 

{

           url 

    {

              path /

status_code 200

             }

        connect_timeout 3

        nb_get_retry 3

        delay_before_retry 3

        }

    }

}

[root@node2 keepalived]# ifconfig

eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.91.130  netmask 255.255.255.0  broadcast 192.168.91.255

        inet6 fe80::20c:29ff:fe2b:9929  prefixlen 64  scopeid 0x20<link>

        ether 00:0c:29:2b:99:29  txqueuelen 1000  (Ethernet)

        RX packets 34791  bytes 10658056 (10.1 MiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 28618  bytes 2324860 (2.2 MiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno16777736:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.91.16  netmask 255.255.255.255  broadcast 0.0.0.0

        ether 00:0c:29:2b:99:29  txqueuelen 1000  (Ethernet)

eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.23.12  netmask 255.255.255.0  broadcast 192.168.23.255

        inet6 fe80::20c:29ff:fe2b:9933  prefixlen 64  scopeid 0x20<link>

        ether 00:0c:29:2b:99:33  txqueuelen 1000  (Ethernet)

        RX packets 66429  bytes 8629069 (8.2 MiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 86941  bytes 6784854 (6.4 MiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno33554984:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

        inet 192.168.23.14  netmask 255.255.255.255  broadcast 0.0.0.0

        ether 00:0c:29:2b:99:33  txqueuelen 1000  (Ethernet)

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536

        inet 127.0.0.1  netmask 255.0.0.0

        inet6 ::1  prefixlen 128  scopeid 0x10<host>

        loop  txqueuelen 0  (Local Loopback)

        RX packets 150  bytes 10963 (10.7 KiB)

        RX errors 0  dropped 0  overruns 0  frame 0

        TX packets 150  bytes 10963 (10.7 KiB)

        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

[root@node2 keepalived]# cat /proc/sys/net/ipv4/ip_forward

1


[root@node2 keepalived]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  192.168.91.15:80 wrr

  -> 192.168.23.16:80             Masq    6      0          0         

  -> 192.168.23.18:80             Masq    3      0          0         

TCP  192.168.91.16:80 wrr

  -> 192.168.23.16:80             Masq    6      0          0         

  -> 192.168.23.19:80             Masq    3      0          0         

Real Server 配置好IP地址。网段:192.168.23.0/24 尾数从16开始偶数的默认网关:192.168.23.15 ,尾数为奇数的默认网关:192.168.23.14

测试:客户端分别访问http://192.168.91.15 和 http://192.168.91.16 得到的结果是15为区域1的服务器 16为区域2的服务器

有没有更好的办法让内部Real Server 不分区,默认网关一样。

问题:客户端只能通过一个外网VIP1访问后端服务器的资源,另一个外网VIP2无法访问,原因在于后端服务器的默认网关只能配一个,默认网关IP地址只能

配置在一台DR上的子接口,即内网VIP。所以采用了折衷的办法:将后端服务器划分成两个区域,网段一样,子网掩码一样,不一样的只是IP地址和

默认网关不一样。使用两个外网VIP和两个内网VIP。不知道是否有更好的办法,

原创文章,作者:jslijb,如若转载,请注明出处:http://www.178linux.com/12698

评论列表(2条)

  • stanley
    stanley 2016-03-12 23:13

    写标签的意识非常赞,代码没有格式化显得非常乱,没有读下去的欲望

    • jslijb
      jslijb 2016-03-15 14:42

      @stanley多谢建议!可能检查不仔细,提交之前是代码是有格式化的!