• Configuring LVS services requires at least four nodes

• Start by installing the httpd service on server22.com and server24.com.

[root@server22 ~]# yum install httpd -y 
[root@server22 ~]# /etc/init.d/httpd start

[root@server24 ~]# yum install httpd -y
[root@server24 ~]# /etc/init.d/httpd start

• Ensure browser access to get the following results
  

• Next, configure the directory node
• First you need to configure a VIP address on the directory

[root@server21 ~]# ip addr add 172.25.23.100/24 dev eth0 
[root@server21 ~]# ip addr show eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:62:3a:95 brd ff:ff:ff:ff:ff:ff
    inet 172.25.23.21/24 brd 172.25.23.255 scope global eth0
    inet 172.25.23.100/24 scope global secondary eth0
    inet6 fe80::5054:ff:fe62:3a95/64 scope link 
       valid_lft forever preferred_lft forever

• After the IP address is provided, the httpd service cannot be accessed properly because the appropriate httpd service rules and backend httpd service nodes are not specified for binding.

[root@server21 ~]# ipvsadm -A -t 172.25.23.100:80 -s rr 
[root@server21 ~]# ipvsadm -a -t 172.25.23.100:80 -r 172.25.23.22:80 -g
[root@server21 ~]# ipvsadm -a -t 172.25.23.100:80 -r 172.25.23.24:80 -g

• You can view the newly added rules

[root@server21 ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.25.23.100:http rr
  -> 172.25.23.22:http            Route   1      0          0         
  -> 172.25.23.24:http            Route   1      0          0  

• Next, check to see if it is dispatched correctly and to which node it is dispatched

[root@server21 ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.25.23.100:http rr
  -> 172.25.23.22:http            Route   1      0          2    [Represents two links]     
  -> 172.25.23.24:http            Route   1      0          2   

• Despite the above configuration, the service is still not accessible properly and will continue to be configured on realserver.

[root@server22 ~]# yum install arptables_jf -y
[root@server22 ~]# arptables -A IN -d 172.25.23.100 -j DROP
[root@server22 ~]# arptables -A OUT -s 172.25.23.100 -j mangle --mangle-ip-s 172.25.23.22
[root@server22 ~]# /etc/init.d/arptables_jf save
Saving current rules to /etc/sysconfig/arptables:          [  OK  ]

[root@server24 ~]#  yum install arptables_jf -y
[root@server24 ~]# arptables -A IN -d 172.25.23.100 -j DROP
[root@server24 ~]# arptables -A OUT -s 172.25.23.100 -j mangle --mangle-ip-s 172.25.23.24 
[root@server24 ~]# /etc/init.d/arptables_jf save
Saving current rules to /etc/sysconfig/arptables:          [  OK  ]

• Next, you need to configure aliases on both network cards

[root@server22 ~]# ifconfig eth0:1 172.25.23.100 netmask 255.255.255.0
[root@server24 ~]# ifconfig eth0:1 172.25.23.100 netmask 255.255.255.0 

• Then refresh the page through the browser
  
  

• Next, configure ldirecotry to implement monitoring status checks for back-end services

• First you need to install the package

[root@server21 ~]# yum install ldirectord-3.9.5-3.1.x86_64.rpm
[root@server21 ~]# cp /usr/share/doc/ldirectord-3.9.5/ldirectord.cf /etc/ha.d/

• Modify Profile

[root@server21 ~]# vim /etc/ha.d/ldirectord.cf 
//Change or add
virtual=172.25.23.100:80
        real=172.25.23.22:80 gate
        real=172.25.23.24:80 gate
        fallback=127.0.0.1:80 gate
        service=http
        scheduler=rr
        #persistent=600
        #netmask=255.255.255.255
        protocol=tcp
        checktype=negotiate
        checkport=80
        request="index.html"
     #  receive="Test Page"
     # virtualhost=www.x.y.z 

• Next stop the service on a node and the dispatch request used will not be dispatched on an abnormal node

[root@server22 ~]# /etc/init.d/httpd stop
Stopping httpd:                                            [  OK  ]

• Service requests are handed over to server24.com to respond
  
• To prevent a single node failure of ldriectory, you can use server20.com and server21.com to configure a highly available cluster of ldirectory, which is configured with high availability here

[root@server21 ~]# vim /etc/ha.d/haresources 
server20.com IPaddr::172.25.23.100/24/eth0 ldirectord httpd

• You also need to copy the configuration information above to another node, and you also need to copy the configuration file for ldirectory

[root@server21 ~]# scp /etc/ha.d/haresources 172.25.23.20:/etc/ha.d/haresources
haresources                                   100% 5969     5.8KB/s   00:00
[root@server21 ~]# scp /etc/ha.d/ldirectord.cf 172.25.23.20:/etc/ha.d/
ldirectord.cf                                 100% 8280     8.1KB/s   00:00 

• You also need to make sure that the ldirectory program exists on the server 20.com node

[root@server20 ~]# /etc/init.d/ldirectord

• Since the cluster service is configured, the resources need to be handed over to the cluster for configuration, so the state of the resources needs to be restored Here

[root@server21 ~]# /etc/init.d/ldirectord stop
Stopping ldirectord... success
[root@server21 ~]# ip addr del 172.25.23.100/24 dev eth0 

• Then start the heartbeat service on top of both nodes

[root@server20 ~]# /etc/init.d/heartbeat start
Starting High-Availability services: INFO:  Resource is stopped
Done.

[root@server21 ~]# /etc/init.d/heartbeat start
Starting High-Availability services: INFO:  Resource is stopped
Done.

• Next, after writing to the server, prompt the user for information

[root@server20 ~]# echo <h2>the server is busying please try later</h2> >/var/www/html/index.html
[root@server21 ~]# echo <h2>the server is busying please try later</h2> >/var/www/html/index.html

• See if heatbeat managed cluster resources are functioning properly

[root@server20 ~]# /etc/init.d/ldirectord status
ldirectord for /etc/ha.d/ldirectord.cf is running with pid: 5126
[root@server20 ~]# /etc/init.d/httpd status
httpd (pid  5154) is running...
[root@server20 ~]# ip addr show eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:03:aa:77 brd ff:ff:ff:ff:ff:ff
    inet 172.25.23.20/24 brd 172.25.23.255 scope global eth0
    inet 172.25.23.100/24 brd 172.25.23.255 scope global secondary eth0
    inet6 fe80::5054:ff:fe03:aa77/64 scope link 
       valid_lft forever preferred_lft forever

• View information about ipvs

[root@server20 ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  localhost:http rr
  -> 172.25.23.22:http            Route   1      0          0         
  -> 172.25.23.24:http            Route   1      0          0   

• Next close the httpd service above the node

[root@server22 ~]# /etc/init.d/httpd  stop
Stopping httpd:                                            [  OK  ]
[root@server24 ~]# /etc/init.d/httpd stop
Stopping httpd:                                            [  OK  ]

• Next, browse to see the page that failed to access
  

• Next, close heartbeat and close ldirectory to configure the keepalived cluster

root@server20 ~]# /etc/init.d/heartbeat stop
Stopping High-Availability services: Done.

[root@server20 ~]# chkconfig heartbeat off
[root@server20 ~]# /etc/init.d/ldirectord stop
Stopping ldirectord... success
[root@server20 ~]# chkconfig ldirectord off

root@server20 ~]# /etc/init.d/heartbeat stop
Stopping High-Availability services: Done.

[root@server21 ~]# chkconfig heartbeat off
[root@server21 ~]# /etc/init.d/ldirectord stop
Stopping ldirectord... success
[root@server21 ~]# chkconfig ldirectord off

*keepalived Requires compilation for installation

[root@server20 keepalived-1.2.24]# yum install libnl-devel libnfnetlink-devel-1.0.0-1.el6.x86_64.rpm [This package requires additional download]-y
[root@server20 keepalived-1.2.24]# ./configure --prefix=/usr/local/keepalived
[root@server20 keepalived-1.2.24]# make 
[root@server20 keepalived-1.2.24]# make install 
[root@server20 keepalived-1.2.24]# scp -r /usr/local/keepalived/ 172.25.23.21:/usr/local/

[root@server20 keepalived-1.2.24]# ln -sv /usr/local/keepalived/etc/keepalived /etc/
`/etc/keepalived' -> `/usr/local/keepalived/etc/keepalived'

[root@server20 keepalived-1.2.24]# ln -sv /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
`/etc/init.d/keepalived' -> `/usr/local/keepalived/etc/rc.d/init.d/keepalived'

[root@server20 keepalived-1.2.24]# chmod +x /etc/init.d/keepalived 

[root@server20 keepalived-1.2.24]# ln -sv  /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/keepalived
`/etc/sysconfig/keepalived' -> `/usr/local/keepalived/etc/sysconfig/keepalived'

[root@server20 keepalived-1.2.24]# ln -sv /usr/local/keepalived/sbin/keepalived /sbin/
`/sbin/keepalived' -> `/usr/local/keepalived/sbin/keepalived'

[root@server20 keepalived-1.2.24]# ln -sv /usr/local/keepalived/etc/ /etc/ 
`/etc/etc' -> `/usr/local/keepalived/etc/'

• Next you need to configure it on server21.com

[root@server21 ~]# ln -sv /usr/local/keepalived/etc/keepalived /etc/
`/etc/keepalived' -> `/usr/local/keepalived/etc/keepalived'
[root@server21 ~]# ln -sv /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
[root@server21 ~]# chmod +x /etc/init.d/keepalived
[root@server21 ~]# ln -sv /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
[root@server21 ~]# ln -sv /usr/local/keepalived/sbin/keepalived /sbin/

• Attempting to start the service on two nodes is certain to be normal

[root@server21 ~]# /etc/init.d/keepalived start
Starting keepalived:                                       [  OK  ]
[root@server21 ~]# /etc/init.d/keepalived stop
Stopping keepalived:                                       [  OK  ]

[root@server20 keepalived-1.2.24]# /etc/init.d/keepalived start
Starting keepalived:                                       [  OK  ]
[root@server20 keepalived-1.2.24]# /etc/init.d/keepalived stop
Stopping keepalived:                                       [  OK  ]

• Next you need to modify the configuration file

[root@server20 ~]# vim /etc/keepalived/keepalived.conf
//Add or modify the following information:

! Configuration File for keepalived

global_defs {
   notification_email {
	root@localhost
   }
   notification_email_from keepalived@server20.com
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   vrrp_strict
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
	172.25.23.100
    }
}

virtual_server 172.25.23.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
#    persistence_timeout 50
    protocol TCP

    real_server 172.25.23.22 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
    real_server 172.25.23.24 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
       	}
   }
}

• Copy this configuration file to server21.com

[root@server20 ~]# scp /etc/keepalived/keepalived.conf 172.25.23.21:/etc/keepalived/keepalived.conf
keepalived.conf                                  100% 1037     1.0KB/s   00:00  

• And make the following changes

Change as follows:
! Configuration File for keepalived

global_defs {
   notification_email {
	root@localhost
   }
   notification_email_from keepalived@server21.com
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   vrrp_strict
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 51
    priority 50
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
	172.25.23.100
    }
}

virtual_server 172.25.23.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
#    persistence_timeout 50
    protocol TCP

    real_server 172.25.23.22 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
    real_server 172.25.23.24 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
       	}
   }
}

• The httpd service for configuring real server is working

[root@server22 ~]# /etc/init.d/httpd  start
Starting httpd: httpd: apr_sockaddr_info_get() failed for server22.com
httpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for ServerName
                                                           [  OK  ]
[root@server24 ~]# /etc/init.d/httpd start
Starting httpd:                                            [  OK  ]

• The keepalived node configuration starts the keepalived service

[root@server20 ~]# /etc/init.d/keepalived restart
Stopping keepalived:                                       [  OK  ]
Starting keepalived:                                       [  OK  ]

[root@server21 ~]# /etc/init.d/keepalived restart
Stopping keepalived:                                       [  OK  ]
Starting keepalived:                                       [  OK  ]

• View Logged Service Startup Information

Apr  4 22:48:13 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:13 server20 Keepalived_vrrp[16094]: VRRP_Instance(VI_1) Sending/queueing gratuitous ARPs on eth0 for 172.25.23.100
Apr  4 22:48:13 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:13 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:13 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:13 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:13 server20 Keepalived_healthcheckers[16093]: Netlink reflector reports IP 172.25.23.100 added
Apr  4 22:48:18 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:18 server20 Keepalived_vrrp[16094]: VRRP_Instance(VI_1) Sending/queueing gratuitous ARPs on eth0 for 172.25.23.100
Apr  4 22:48:18 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:18 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:18 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:48:18 server20 Keepalived_vrrp[16094]: Sending gratuitous ARP on eth0 for 172.25.23.100

• Virtual IP services are normally accessible through browsers
  

• Observe the migration of services by closing keepalived on server20.com
• Serr20.com shows that the service has stopped

Apr  4 22:57:38 server20 Keepalived_vrrp[16094]: VRRP_Instance(VI_1) removing protocol VIPs.
Apr  4 22:57:38 server20 Keepalived_healthcheckers[16093]: Netlink reflector reports IP 172.25.23.100 removed
Apr  4 22:57:38 server20 Keepalived_healthcheckers[16093]: Removing service [172.25.23.22]:80 from VS [172.25.23.100]:80
Apr  4 22:57:38 server20 Keepalived_healthcheckers[16093]: Removing service [172.25.23.24]:80 from VS [172.25.23.100]:80
Apr  4 22:57:38 server20 Keepalived_healthcheckers[16093]: Stopped

• Serr21.com shows above that the service is being configured

Apr  4 22:57:45 server21 Keepalived_vrrp[6283]: VRRP_Instance(VI_1) Sending/queueing gratuitous ARPs on eth0 for 172.25.23.100
Apr  4 22:57:45 server21 Keepalived_vrrp[6283]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:57:45 server21 Keepalived_vrrp[6283]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:57:45 server21 Keepalived_vrrp[6283]: Sending gratuitous ARP on eth0 for 172.25.23.100
Apr  4 22:57:45 server21 Keepalived_vrrp[6283]: Sending gratuitous ARP on eth0 for 172.25.23.100

• Address is already properly configured

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:62:3a:95 brd ff:ff:ff:ff:ff:ff
    inet 172.25.23.21/24 brd 172.25.23.255 scope global eth0
    inet 172.25.23.100/32 scope global eth0

• The rules for ipvsadm have also been transferred

[root@server21 ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.25.23.100:http rr
  -> 172.25.23.22:http            Route   1      0          0         
  -> 172.25.23.24:http            Route   1      0          0   

• Access to services is also normal;