mysqlkeepalivedmha作用

mysqlkeepalivedmha作用

lvs keepalived mysql 什么场景

MHA主要负责MySQL的高可用，而LVS主要对多个MHA进行负载均衡，防止单个MHA节点压力过大以及发生单点故障。Keepalived主要负责防止LVS服务器宕机。这是一个高可用的集群。

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keepalived mysql 主从能负载均衡么

部署完成之后，通过VIP：192.168.21.254，根据LVS调度算法来访问后端真实的MySQL从服务器，实现负载均衡。第一部分：分别在两台MySQL从服务器上操作一、关闭SELINUXvi /etc/selinux/config#SELINUX=enforcing #注释掉#SELINUXTYPE=targeted #注释掉SELINUX=disabled #增加:wq! #保存退出setenforce 0 #使配置立即生效二、配置防火墙，开启3306端口vi /etc/sysconfig/iptables #编辑-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT #允许3306端口通过防火墙:wq! #保存退出/etc/init.d/iptables restart #重启防火墙使配置生效www.osyunwei温馨提醒：qihang01原创内容 版权所有,转载请注明出处及原文链接三、绑定LVS虚拟服务器(VIP)：192.168.21.254到lo:0vi /etc/rc.d/init.d/realserver #编辑，添加以下代码##################################################!/bin/sh# chkconfig: - 80 90# description:realserver# mysql_vip start realservermysql_vip=192.168.21.254 #LVS虚拟服务器(VIP). /etc/rc.d/init.d/functionscase "$1" inifconfig lo:0 $mysql_vip netmask 255.255.255.255 broadcast $mysql_vip/sbin/route add -host $mysql_vip dev lo:0echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignoreecho "2" >/proc/sys/net/ipv4/conf/lo/arp_announceecho "1" >/proc/sys/net/ipv4/conf/all/arp_ignoreecho "2" >/proc/sys/net/ipv4/conf/all/arp_announcesysctl -p >/dev/null 2>&1echo "RealServer Start OK"ifconfig lo:0 downroute del $mysql_vip >/dev/null 2>&1echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignoreecho "0" >/proc/sys/net/ipv4/conf/lo/arp_announceecho "0" >/proc/sys/net/ipv4/conf/all/arp_ignoreecho "0" >/proc/sys/net/ipv4/conf/all/arp_announceecho "RealServer Stoped"echo "Usage: $0 {start|stop}"#################################################chmod +x /etc/rc.d/init.d/realserver #添加脚本执行权限chkconfig realserver on #添加开机启动/etc/rc.d/init.d/realserver start #开启，参数stop为关闭四、调整服务器参数，使LVS虚拟服务器(VIP)忽略ARP广播包vi /f #编辑net.ipv4.ip_forward= 1 #修改0为1，开启转发f.lo.arp_ignore= f.lo.arp_announce= f.all.arp_ignore= f.all.arp_announce= 2:wq! #保存退出/sbin/sysctl -p#使配置立即生效五、设置能够远程监控MySQL主从同步状态的MySQL用户和密码mysql -u root -p #进入MySQL控制台insert into mysql.user(Host,User,Password) values('localhost','checkslave',password('123456'));#新建账户checkslave，密码123456flush privileges;#刷新系统授权表grant all on *.* to 'checkslave'@'192.168.21.129' identified by '123456' with grant option;#允许账户checkslave从LVS主服务器192.168.21.129连接到数据库服务器grant all on *.* to 'checkslave'@'192.168.21.130' identified by '123456' with grant option;#允许账户checkslave从LVS从服务器192.168.21.130连接到数据库服务器第二部分：分别在两台LVS主备服务器上操作一、关闭SElinux、配置防火墙1、vi /etc/selinux/config#SELINUX=enforcing #注释掉#SELINUXTYPE=targeted #注释掉SELINUX=disabled #增加:wq! #保存退出setenforce 0 #使配置立即生效2、vi /etc/sysconfig/iptables #编辑-A RH-Firewall-1-INPUT -d 224.0.0.18 -j ACCEPT #允许VRRP(虚拟路由器冗余协议)组播地址通信-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT #允许3306端口通过防火墙:wq! #保存退出/etc/init.d/iptables restart #重启防火墙使配置生效二、安装lvs软件yum install ipvsadm #Linux 2.6内核已经集成了lvs软件，此处ipvsadm为lvs管理工具modprobe ip_vs #加载ip_vs三、安装keepalivedyum install gcc gcc-c++ make openssl-devel kernel-devel ncurses-devel #安装编译工具包下载keeplived：上传keepalived-1.2.到/usr/local/src目录cd /usr/local/srctar zxvf keepalived-1.2.d keepalived-1.2.12./configure #配置，必须看到以下提示，说明配置正确，才能继续安装Use IPVS Framework : YesIPVS sync daemon support : YesUse VRRP Framework: Yesmake #编辑make install #安装cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/mkdir /etc/keepalivedcp /usr/local/etc/f /etc/keepalived/cp /usr/local/sbin/keepalived /usr/sbin/cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/chmod +x /etc/rc.d/init.d/keepalived #添加执行权限chkconfig keepalived on #设置开机启动service keepalived start #启动service keepalived stop #关闭service keepalived restart #重启四、安装perl、perl-DBI、DBD-mysql模块以及MySQL客户端#perl脚本连接MySQL数据库需要yum install perl perl-DBI perl-DBD-MySQL mysql #执行此命令安装vi /tmp/test_perl.pl#!/usr/bin/perlprint "Hello, world!n";:wq! #保存退出perl /tmp/test_perl.pl #运行测试脚本，如果出现：Hello,world! 说明perl安装成功perldoc DBI #查看DBI模块是否安装perldoc DBD::mysql#查看DBD::mysql模块是否安装五、配置keepalivedcp /etc/f /etc/f-bakvi /etc/f #编辑，修改为以下代码##################################################################################################! Configuration File for keepalivedglobal_defs {notification_email {acassen@firewall.locfailover@firewall.locsysadmin@firewall.locnotification_email_from Alexandre.Cassen@firewall.locsmtp_server 192.168.200.1smtp_connect_timeout 30router_id LVS_DEVELvrrp_instance VI_1 {state MASTER #LVS备机修改为BACKUPinterface eth0virtual_router_id 51priority 100 #LVS备机修改为80advert_int 1authentication {auth_type PASSauth_pass 1111virtual_ipaddress {192.168.21.254notify_master "/etc/keepalived/clean_arp.sh" #LVS主备机都为notify_mastervirtual_server 192.168.21.254 3306 {delay_loop 30lb_algo wlclb_kind DR#nat_mask 255.255.255.0persistence_timeout 120protocol TCPreal_server 192.168.21.127 3306 {weight 1MISC_CHECK {misc_path "/etc/keepalived/check_slave.pl 192.168.21.127"misc_dynamicreal_server 192.168.21.128 3306 {weight 1MISC_CHECK {misc_path "/etc/keepalived/check_slave.pl 192.168.21.128"misc_dynamic##################################################################################################:wq! #保存退出www.osyunwei温馨提醒：qihang01原创内容 版权所有,转载请注明出处及原文链接六、设置MySQL主从监控脚本check_slave.plvi /etc/keepalived/check_slave.pl #编辑，添加以下代码###################################################################################################!/usr/bin/perl -wuse DBI;use DBD::mysql;# CONFIG VARIABLES$SBM = 120;$db = "osyunweidb";$host = $ARGV[0];$port = 3306;$user = "checkslave";$pw = "123456";# SQL query$query = "show slave status";$dbh = DBI->connect("DBI:mysql:$db:$host:$port", $user, $pw, { RaiseError => 0,PrintError => 0 });if (!defined($dbh)) {$sqlQuery = $dbh->prepare($query);$sqlQuery->execute;$Slave_IO_Running = "";$Slave_SQL_Running = "";$Seconds_Behind_Master = "";while (my $ref = $sqlQuery->fetchrow_hashref()) {$Slave_IO_Running = $ref->{'Slave_IO_Running'};$Slave_SQL_Running = $ref->{'Slave_SQL_Running'};$Seconds_Behind_Master = $ref->{'Seconds_Behind_Master'};$sqlQuery->finish;$dbh->disconnect();if ( $Slave_IO_Running eq "No" || $Slave_SQL_Running eq "No" ) {} else {if ( $Seconds_Behind_Master > $SBM ) {} else {##################################################################################################:wq! #保存退出chmod +x /etc/keepalived/check_slave.pl #添加脚本执行权限七、设置更新LVS虚拟服务器(VIP)地址的arp记录到网关脚本vi /etc/keepalived/clean_arp.sh #编辑，添加以下代码#!/bin/shVIP=192.168.21.254GATEWAY=192.168.21.2/sbin/arping -I eth0 -c 5 -s $VIP $GATEWAY &>/dev/null:wq! #保存退出chmod +x /etc/keepalived/clean_arp.sh #添加脚本执行权限八、测试LVS+Keepalived是否正常运行service keepalived restart #在两台LVS主备服务器上重启keepalivedipvsadm -L #在两台LVS主备服务器上执行此命令，ip addr show #在两台LVS主备服务器上执行此命令，#从图中可以看到VIP：192.168.21.254现在指向的是LVS主服务器1、关闭LVS主服务器的keepalived服务，查看LVS备服务器是否正常接管keepalivedservice keepalived stop #在LVS主服务器上运行此时，在两台LVS主备服务器上执行ip addr show命令，www.osyunwei温馨提醒：qihang01原创内容 版权所有,转载请注明出处及原文链接可以看到VIP：192.168.21.254现在指向的是LVS备服务器，说明LVS备服务器已经接管keepalived，测试成功。2、停止MySQL从服务器192.168.21.127上面的主从同步服务mysql -u root -p #进入MySQL控制台slave start; #停止同步在LVS备服务器执行ipvsadm -L命令，可以看到MySQL从服务器192.168.21.127已经从负载均衡列表中被剔除了，测试成功。3、从客户端连接LVS虚拟服务器(VIP)：192.168.21.254telnet 192.168.21.254 3306 #执行此命令，说明测试成功。tail -f /var/log/messages #查看LVS日志信息至此，LVS+Keepalived实现MySQL从库读操作负载均衡配置完成。

有什么作用？柚子的作用？柚子的作用，有什么作用？

宝妈你好,柚子是秋冬非常好的水果,富含维生素、矿物质和果肉粗纤维,吃了能美容美肤、防止皮肤干燥,还能消食化痰防便秘,也是减肥期必备水果。当然,柚子性寒,寒性体质的女性不宜吃太多,同时柚子与某些药物有冲突,比如治疗高血压的药物。

有什么作用？柚子的作用？柚子的作用，有什么作用？

宝妈你好,柚子是秋冬非常好的水果,富含维生素、矿物质和果肉粗纤维,吃了能美容美肤、防止皮肤干燥,还能消食化痰防便秘,也是减肥期必备水果。当然,柚子性寒,寒性体质的女性不宜吃太多,同时柚子与某些药物有冲突,比如治疗高血压的药物。