LVS+Keepalived效率最高的群集（实战）
发表于：2024-09-23 作者：千家信息网编辑
千家信息网最后更新 2024年09月23日，LVS+Keepalived群集环境准备：DR1 主：192.168.100.101---->CentOS 7-2DR2 备：192.168.100.102---->CentOS 7-3web1：19
千家信息网最后更新 2024年09月23日LVS+Keepalived效率最高的群集（实战）
LVS+Keepalived群集
环境准备：
DR1 主：192.168.100.101---->CentOS 7-2
DR2 备：192.168.100.102---->CentOS 7-3
web1：192.168.100.111---->CentOS 7-4
web1：192.168.100.112---->CentOS 7-5
vip：192.168.100.10
客户机：192.168.100.10
提前准备在线yum源的软件安装：
CentOS 7-2：[root@localhost ~]# yum install ipvsadm keepalived -y[root@localhost ~]# cd /etc/keepalived/[root@localhost keepalived]# lskeepalived.conf//安装完成后验证有没有此主配置文件CentOS 7-3：[root@localhost ~]# yum install ipvsadm keepalived -y[root@localhost ~]# cd /etc/keepalived/[root@localhost keepalived]# lskeepalived.conf//安装完成后验证有没有此主配置文件CentOS 7-4：[root@localhost ~]# yum install httpd -yCentOS 7-5：[root@localhost ~]# yum install httpd -y将所有网卡改为仅主机模式，同时修改网卡配置文件：
**CentOS 7-2：**[root@localhost keepalived]# vim /etc/sysconfig/network-scripts/ifcfg-ens33BROWSER_ONLY="no"BOOTPROTO="static" //改dhcp为static......此处省略多行ONBOOT="yes"IPADDR=192.168.100.101 //在末行按o，在下行插入以下内容NETMASK=255.255.255.0GATEWAY=192.168.100.1//修改完成后输入:wq保存退出[root@localhost keepalived]# vim /etc/sysconfig/network-scripts/ifcfg-ens33[root@localhost keepalived]# service network restart Restarting network (via systemctl): [ 确定 ][root@localhost keepalived]# ifconfigens33: flags=4163 mtu 1500 inet 192.168.100.101 netmask 255.255.255.0 broadcast 192.168.100.255//确认下网卡是否修改完成**CentOS 7-3：**[root@localhost keepalived]# vim /etc/sysconfig/network-scripts/ifcfg-ens33BROWSER_ONLY="no"BOOTPROTO="static" //改dhcp为static......此处省略多行ONBOOT="yes"IPADDR=192.168.100.102 //在末行按o，在下行插入以下内容NETMASK=255.255.255.0GATEWAY=192.168.100.1//修改完成后输入:wq保存退出[root@localhost keepalived]# vim /etc/sysconfig/network-scripts/ifcfg-ens33[root@localhost keepalived]# service network restart Restarting network (via systemctl): [ 确定 ][root@localhost keepalived]# ifconfigens33: flags=4163 mtu 1500 inet 192.168.100.102 netmask 255.255.255.0 broadcast 192.168.100.255//确认下网卡是否修改完成//此时可以同网段内测试ping通，看地址是否生效：[root@localhost keepalived]# ping 192.168.100.101PING 192.168.100.101 (192.168.100.101) 56(84) bytes of data.64 bytes from 192.168.100.101: icmp_seq=1 ttl=64 time=0.658 ms64 bytes from 192.168.100.101: icmp_seq=2 ttl=64 time=1.21 ms//此时两台调度主机相互连通 **CentOS 7-4：**[root@localhost ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens33BROWSER_ONLY="no"BOOTPROTO="static" //改dhcp为static......此处省略多行ONBOOT="yes"IPADDR=192.168.100.111 //在末行按o，在下行插入以下内容NETMASK=255.255.255.0GATEWAY=192.168.100.1//修改完成后输入:wq保存退出[root@localhost ~]# service network restart Restarting network (via systemctl): [ 确定 ][root@localhost ~]# ifconfigens33: flags=4163 mtu 1500 inet 192.168.100.111 netmask 255.255.255.0 broadcast 192.168.100.255//确认下网卡是否修改完成**CentOS 7-5：**[root@localhost ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens33BROWSER_ONLY="no"BOOTPROTO="static" //改dhcp为static......此处省略多行ONBOOT="yes"IPADDR=192.168.100.112 //在末行按o，在下行插入以下内容NETMASK=255.255.255.0GATEWAY=192.168.100.1//修改完成后输入:wq保存退出[root@localhost ~]# service network restart Restarting network (via systemctl): [ 确定 ][root@localhost ~]# ifconfigens33: flags=4163 mtu 1500 inet 192.168.100.112 netmask 255.255.255.0 broadcast 192.168.100.255//确认下网卡是否修改完成//此时可以同网段内测试ping通，看地址是否生效：[root@localhost ~]# ping 192.168.100.111PING 192.168.100.111 (192.168.100.111) 56(84) bytes of data.64 bytes from 192.168.100.111: icmp_seq=1 ttl=64 time=0.913 ms64 bytes from 192.168.100.111: icmp_seq=2 ttl=64 time=0.830 ms//此时两台节点服务器相互连通 调度服务器CentOS 7-2上的修改：
[root@localhost keepalived]# vim /etc/sysctl.conf //在末行下插入以下内容net.ipv4.ip_forward=1 //开启路由转发功能net.ipv4.conf.all.send_redirects = 0 //proc响应关闭重定向功能net.ipv4.conf.default.send_redirects = 0net.ipv4.conf.ens33.send_redirects = 0//修改完成后输入:wq保存退出[root@localhost keepalived]# sysctl -p //生效net.ipv4.ip_forward = 1net.ipv4.conf.all.send_redirects = 0net.ipv4.conf.default.send_redirects = 0net.ipv4.conf.ens33.send_redirects = 0创建虚拟网卡：
[root@localhost ens33]# cd /etc/sysconfig/network-scripts/[root@localhost network-scripts]# lsifcfg-ens33 ifdown-ppp ifup-ib ifup-Teamifcfg-lo ifdown-routes ifup-ippp ifup-TeamPortifdown ifdown-sit ifup-ipv6 ifup-tunnel......此处省略多行[root@localhost network-scripts]# cp ifcfg-ens33 ifcfg-ens33:0[root@localhost network-scripts]# vim ifcfg-ens33:0//先按50dd删除所有内容，再插入以下内容DEVICE=ens33:0ONBOOT=yesIPADDR=192.168.100.10NETMASK=255.255.255.0//修改完成后输入:wq保存退出[root@localhost network-scripts]# ifup ens33:0 //启用虚拟网卡[root@localhost network-scripts]# ifconfigens33: flags=4163 mtu 1500ens33:0: flags=4163 mtu 1500 inet 192.168.100.10 netmask 255.255.255.0 broadcast 192.168.100.255 ether 00:0c:29:c2:51:f6 txqueuelen 1000 (Ethernet)//这个是到时候要用来做虚拟IP的，也是访问的入站口[root@localhost network-scripts]# cd /etc/init.d/[root@localhost init.d]# vim dr.sh #!/bin/bashGW=192.168.100.1VIP=192.168.100.10RIP1=192.168.100.111RIP2=192.168.100.112 case "$1" instart) /sbin/ipvsadm --save > /etc/sysconfig/ipvsadm systemctl start ipvsadm /sbin/ifconfig ens33:0 $VIP broadcast $VIP netmask 255.255.255.255 broadcast $VIP up /sbin/route add -host $VIP dev ens33:0 /sbin/ipvsadm -A -t $VIP:80 -s rr /sbin/ipvsadm -a -t $VIP:80 -r $RIP1:80 -g /sbin/ipvsadm -a -t $VIP:80 -r $RIP2:80 -g echo "ipvsadm starting ---------------------[ok]" ;; stop) /sbin/ipvsadm -C systemctl stop ipvsadm ifconfig ens33:0 down route del $VIP echo "ipvsadm stoped--------------------[ok]" ;; status) if [ ! -e /var/lock/subsys/ipvsadm ];then echo "ipvsadm stoped--------------" exit 1 else echo "ipvsadm Runing-----------[ok]" fi ;; *) echo "Usage: $0 {start|stop|status}" exit 1 ;; esac exit 0//修改完成后输入:wq保存退出[root@localhost init.d]# chmod +x dr.sh [root@localhost init.d]# service dr.sh startipvsadm starting ---------------------[ok][root@localhost init.d]# systemctl stop firewalld.service [root@localhost init.d]# setenforce 0 节点服务器CentOS 7-4的操作：
[root@localhost ~]# rpm -q httpdhttpd-2.4.6-90.el7.centos.x86_64[root@localhost ~]# systemctl start httpd[root@localhost ~]# systemctl stop firewalld.service [root@localhost ~]# setenforce 0[root@localhost ~]# cd /var/www/html/[root@localhost html]# echo "this is accp web" > index.html[root@localhost html]# cd /etc/sysconfig/network-scripts/[root@localhost network-scripts]# lsifcfg-ens33 ifdown-ppp ifup-ib ifup-Teamifcfg-lo ifdown-routes ifup-ippp ifup-TeamPort[root@localhost network-scripts]# cp ifcfg-lo ifcfg-lo:0[root@localhost network-scripts]# vim ifcfg-lo:0//把不需要的都删除，然后做如下修改DEVICE=lo:0IPADDR=192.168.100.10NETMASK=255.255.255.0ONBOOT=yes//修改完成后输入:wq保存退出[root@localhost network-scripts]# cd /etc/init.d/[root@localhost init.d]# vim web.sh#!/bin/bashVIP=192.168.100.10case "$1" instart) /sbin/ifconfig lo:0 $VIP netmask 255.255.255.255 broadcast $VIP /sbin/route add -host $VIP dev 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 sysctl -p >/dev/null 2>&1 echo "RealServer Start OK" ;;stop) /sbin/ifconfig lo:0 down /sbin/route del $VIP /dev/null 2>&1 echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce echo "RealServer Stoped" ;;*) echo "Usage: $0 {start|stop}" exit 1 ;;esacexit 0//修改完成后输入:wq保存退出[root@localhost init.d]# chmod +x web.sh [root@localhost init.d]# service web.sh start RealServer Start OK [root@localhost init.d]# ifup lo:0[root@localhost init.d]# ifconfiglo:0: flags=73 mtu 65536 inet 192.168.100.10 netmask 255.255.255.0 loop txqueuelen 1 (Local Loopback)//此时以上内容显示虚拟网卡启用成功 [root@localhost init.d]# firefox "http://127.0.0.1" &[1] 8587 //进程号随机//火狐浏览器放在后台自动执行，进程为8587，浏览器会自动弹出，会显示我们之前写入的网页内容 
重启脚本：
[root@localhost init.d]# service web.sh stopSIOCDELRT: No such deviceRealServer Stopd[1]- 完成 firefox "http://127.0.0.1"[2]+ 完成 firefox "http://127.0.0.1"[root@localhost init.d]# service web.sh start RealServer Start OK 此时第一台节点服务器配置完成！
节点服务器CentOS 7-5的操作：
[root@localhost ~]# rpm -q httpdhttpd-2.4.6-90.el7.centos.x86_64[root@localhost ~]# systemctl start httpd[root@localhost ~]# systemctl stop firewalld.service [root@localhost ~]# setenforce 0[root@localhost html]# cd /etc/sysconfig/network-scripts/[root@localhost network-scripts]# lsifcfg-ens33 ifdown-ppp ifup-ib ifup-Teamifcfg-lo ifdown-routes ifup-ippp ifup-TeamPort[root@localhost network-scripts]# cp ifcfg-lo ifcfg-lo:0[root@localhost network-scripts]# vim ifcfg-lo:0//把不需要的都删除，然后做如下修改DEVICE=lo:0IPADDR=192.168.100.10NETMASK=255.255.255.0ONBOOT=yes//修改完成后输入:wq保存退出[root@localhost ~]# cd /var/www/html/[root@localhost html]# echo "this is benet web" > index.html[root@localhost network-scripts]# cd /etc/init.d/[root@localhost init.d]# vim web.sh#!/bin/bashVIP=192.168.100.10case "$1" instart) /sbin/ifconfig lo:0 $VIP netmask 255.255.255.255 broadcast $VIP /sbin/route add -host $VIP dev 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 sysctl -p >/dev/null 2>&1 echo "RealServer Start OK" ;;stop) /sbin/ifconfig lo:0 down /sbin/route del $VIP /dev/null 2>&1 echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce echo "RealServer Stoped" ;;*) echo "Usage: $0 {start|stop}" exit 1 ;;esacexit 0//修改完成后输入:wq保存退出[root@localhost init.d]# chmod +x web.sh [root@localhost init.d]# service web.sh start RealServer Start OK [root@localhost init.d]# ifup lo:0[root@localhost html]# firefox "http://127.0.0.1" &[1] 8767 //进程号随机//火狐浏览器放在后台自动执行，进程为8767，浏览器会自动弹出，会显示我们之前写入的网页内容 !
重启脚本：
[root@localhost init.d]# service web.sh stopSIOCDELRT: No such deviceRealServer Stopd[1]+ 完成 firefox "http://127.0.0.1"[root@localhost init.d]# service web.sh start RealServer Start OK 使用win7-1客户机验证LVS：
将网卡设置为仅主机，并将网关ipv4绑定为静态地址：
C:\Users\zhou>ping 192.168.100.10正在 Ping 192.168.100.10 具有 32 字节的数据:来自 192.168.100.10 的回复: 字节=32 时间<1ms TTL=64来自 192.168.100.10 的回复: 字节=32 时间<1ms TTL=64来自 192.168.100.10 的回复: 字节=32 时间=1ms TTL=64来自 192.168.100.10 的回复: 字节=32 时间=1ms TTL=64192.168.100.10 的 Ping 统计信息: 数据包: 已发送 = 4，已接收 = 4，丢失 = 0 (0% 丢失)，往返行程的估计时间(以毫秒为单位): 最短 = 0ms，最长 = 1ms，平均 = 0ms测试调度服务器CentOS 7-2与两台web服务器的联通：
[root@localhost init.d]# ping 192.168.100.111PING 192.168.100.111 (192.168.100.111) 56(84) bytes of data.64 bytes from 192.168.100.111: icmp_seq=1 ttl=64 time=0.433 ms64 bytes from 192.168.100.111: icmp_seq=2 ttl=64 time=0.501 ms64 bytes from 192.168.100.111: icmp_seq=3 ttl=64 time=1.10 ms^C--- 192.168.100.111 ping statistics ---3 packets transmitted, 3 received, 0% packet loss, time 2001msrtt min/avg/max/mdev = 0.433/0.681/1.109/0.303 ms[root@localhost init.d]# ping 192.168.100.112PING 192.168.100.112 (192.168.100.112) 56(84) bytes of data.64 bytes from 192.168.100.112: icmp_seq=1 ttl=64 time=0.885 ms64 bytes from 192.168.100.112: icmp_seq=2 ttl=64 time=0.883 ms64 bytes from 192.168.100.112: icmp_seq=3 ttl=64 time=0.973 ms^C--- 192.168.100.112 ping statistics ---3 packets transmitted, 3 received, 0% packet loss, time 2002msrtt min/avg/max/mdev = 0.883/0.913/0.973/0.054 ms//状态均为可达，说明配置无问题此时在win7-1的浏览器中输入:http://192.168.100.10/会先显示this is benet web，再次刷新之后会显示this is accp web，此时说明LVS负载均衡成功！
调度服务器CentOS 7-2上keepalived的操作：
[root@localhost init.d]# cd /etc/keepalived/[root@localhost keepalived]# lskeepalived.conf[root@localhost keepalived]# vim keepalived.conf 上部省略多行smtp_server 127.0.0.1router_id LVS_01 //改为LVS_01vrrp_instance VI_1 {......此处省略多行 auth_pass abc123 //密码改为后面的abc123virtual_ipaddress { 192.168.100.10virtual_server 192.168.100.10 80 { //虚拟地址加端口 delay_loop 6 lb_algo rr lb_kind DR //此处改为DR persistence_timeout 50 protocol TCP //此处修改为TCP real_server 192.168.100.111 80 { //web1地址 weight 1 TCP_CHECK { connect_port 80 connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } }//此处9yy在下行插入，然后修改IP即可 real_server 192.168.100.112 80 { //web2地址 weight 1 TCP_CHECK { connect_port 80 connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } }//修改完成后输入:wq保存退出[root@localhost keepalived]# systemctl start keepalived//查看网卡状态 [root@localhost keepalived]# ip add show dev ens33:02: ens33: mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:c2:51:f6 brd ff:ff:ff:ff:ff:ff inet 192.168.100.101/24 brd 192.168.100.255 scope global ens33 valid_lft forever preferred_lft forever inet 192.168.100.10/32 brd 192.168.100.10 scope global ens33:0 valid_lft forever preferred_lft forever inet6 fe80::6a0c:e6a0:7978:3543/64 scope link valid_lft forever preferred_lft forever 调度服务器CentOS 7-3上的修改：
[root@localhost keepalived]# systemctl stop firewalld.service [root@localhost keepalived]# setenforce 0[root@localhost keepalived]# vim /etc/sysctl.conf //在末行下插入以下内容net.ipv4.ip_forward=1 //开启路由转发功能net.ipv4.conf.all.send_redirects = 0 //proc响应关闭重定向功能net.ipv4.conf.default.send_redirects = 0net.ipv4.conf.ens33.send_redirects = 0//修改完成后输入:wq保存退出[root@localhost keepalived]# sysctl -p //生效net.ipv4.ip_forward = 1net.ipv4.conf.all.send_redirects = 0net.ipv4.conf.default.send_redirects = 0net.ipv4.conf.ens33.send_redirects = 0[root@localhost keepalived]# sysctl -pnet.ipv4.ip_forward = 1net.ipv4.conf.all.send_redirects = 0net.ipv4.conf.default.send_redirects = 0net.ipv4.conf.ens33.send_redirects = 0**创建虚拟网卡：**[root@localhost ens33]# cd /etc/sysconfig/network-scripts/[root@localhost network-scripts]# lsifcfg-ens33 ifdown-ppp ifup-ib ifup-Teamifcfg-lo ifdown-routes ifup-ippp ifup-TeamPortifdown ifdown-sit ifup-ipv6 ifup-tunnel......此处省略多行[root@localhost network-scripts]# cp ifcfg-ens33 ifcfg-ens33:0[root@localhost network-scripts]# vim ifcfg-ens33:0//先按50dd删除所有内容，再插入以下内容DEVICE=ens33:0ONBOOT=yesIPADDR=192.168.100.10NETMASK=255.255.255.0//修改完成后输入:wq保存退出[root@localhost network-scripts]# ifup ens33:0 //启用虚拟网卡ERROR : [/etc/sysconfig/network-scripts/ifup-eth] Error, some other host (00:0C:29:C2:51:F6) already uses address 192.168.100.10.//此时会报错，只要我们重启网络服务就可以再次启动虚拟网卡了[root@localhost network-scripts]# service network restart Restarting network (via systemctl): [ 确定 ][root@localhost network-scripts]# ifup ens33:0[root@localhost network-scripts]# ifconfigens33: flags=4163 mtu 1500ens33:0: flags=4163 mtu 1500 inet 192.168.100.10 netmask 255.255.255.0 broadcast 192.168.100.255 ether 00:0c:29:c2:51:f6 txqueuelen 1000 (Ethernet)//这个是到时候要用来做虚拟IP的，也是访问的入站口[root@localhost network-scripts]# cd /etc/init.d/[root@localhost init.d]# vim dr.sh #!/bin/bashGW=192.168.100.1VIP=192.168.100.10RIP1=192.168.100.111RIP2=192.168.100.112 case "$1" instart) /sbin/ipvsadm --save > /etc/sysconfig/ipvsadm systemctl start ipvsadm /sbin/ifconfig ens33:0 $VIP broadcast $VIP netmask 255.255.255.255 broadcast $VIP up /sbin/route add -host $VIP dev ens33:0 /sbin/ipvsadm -A -t $VIP:80 -s rr /sbin/ipvsadm -a -t $VIP:80 -r $RIP1:80 -g /sbin/ipvsadm -a -t $VIP:80 -r $RIP2:80 -g echo "ipvsadm starting ---------------------[ok]" ;; stop) /sbin/ipvsadm -C systemctl stop ipvsadm ifconfig ens33:0 down route del $VIP echo "ipvsadm stoped--------------------[ok]" ;; status) if [ ! -e /var/lock/subsys/ipvsadm ];then echo "ipvsadm stoped--------------" exit 1 else echo "ipvsadm Runing-----------[ok]" fi ;; *) echo "Usage: $0 {start|stop|status}" exit 1 ;; esac exit 0//修改完成后输入:wq保存退出[root@localhost init.d]# chmod +x dr.sh [root@localhost init.d]# service dr.sh startipvsadm starting ---------------------[ok][root@localhost init.d]# cd /etc/keepalived/[root@localhost keepalived]# vim keepalived.conf smtp_server 127.0.0.1· //自身的 router_id LVS_02 //序号写02 vrrp_skip_check_adv_addr interface eth0virtual_router_id 10 //id改为10 priority 99 //优先级为100以下 advert_int 1 authentication { auth_type PASS auth_pass abc123 //修改密码virtual_ipaddress { 192.168.100.10 //删除另外三行，修改IPvirtual_server 192.168.100.10 80 { //修改IP和端口 delay_loop 6 lb_algo rr lb_kind DR //NAT改为DR persistence_timeout 50 protocol TCP real_server 192.168.100.111 80 { //web1地址 weight 1 TCP_CHECK { //下面的内容8dd删除8行 connect_port 80 //添加这行 connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } }//此处9yy在下行插入，然后修改IP即可 real_server 192.168.100.112 80 { //web2地址 weight 1 TCP_CHECK { connect_port 80 connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } }//修改完成后输入:wq保存退出[root@localhost keepalived]# systemctl start keepalived keepalived双机热备验证：
1.把调度服务器1：CentOS 7-1服务关闭：ifdown ens33:0
2.再回到win7客户端中使用cmd命令提示符ping：192.168.100.10，如果现在还可以ping通就说明keepalived双机热备成功顶上
此时试验成功！
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