1、集群类型
LB:Load Balance 负载均衡 LVS/HAProxy/nginx(http/upstream, stream/upstream) HA:High Availability 高可用集群 数据库、Zookeeper、Redis KeepAlived 通用的高可用集群 SPoF: Single Point of Failure,解决单点故障 HPC:High Performance Computing 高性能集群 https://www.top500.org
2、Keepalived 介绍
vrrp 协议的软件实现,原生设计目的为了高可用 ipvs服务 官网:http://keepalived.org/ 功能: 基于vrrp协议完成地址流动 为vip地址所在的节点生成ipvs规则(在配置文件中预先定义) 为ipvs集群的各RS做健康状态检测 基于脚本调用接口完成脚本中定义的功能,进而影响集群事务,以此支持nginx、haproxy等服务
用户空间核心组件: vrrp stack:VIP消息通告 checkers:监测 Real Server system call:实现 vrrp 协议状态转换时调用脚本的功能 SMTP:邮件组件 IPVS wrapper:生成 IPVS 规则 Netlink Reflector:网络接口 WatchDog:监控进程
控制组件:提供keepalived.conf 的解析器,完成Keepalived配置
IO复用器:针对网络目的而优化的自己的线程抽象
内存管理组件:为某些通用的内存管理功能(例如分配,重新分配,发布等)提供访问权限
各节点时间必须同步:ntp, chrony
关闭防火墙及SELinux
各节点之间可通过主机名互相通信:非必须
建议使用/etc/hosts文件实现:非必须
各节点之间的root用户可以基于密钥认证的ssh服务完成互相通信:非必须
2-1、Keepalived 相关文件
软件包名:keepalived 主程序文件:/usr/sbin/keepalived 主配置文件:/etc/keepalived/keepalived.conf 配置文件示例:/usr/share/doc/keepalived/ Unit File:/lib/systemd/system/keepalived.service Unit File的环境配置文件: /etc/sysconfig/keepalived CentOS /etc/default/keepalived Ubuntu
注意:CentOS 7 上有 bug,可能有下面情况出现
systemctl restart keepalived #新配置可能无法生效
systemctl stop keepalived;systemctl start keepalived #无法停止进程,需要 kill停止
3、Keepalived 安装
3-1、包安装
[root@ka1 ~]#vim /etc/hosts
10.0.0.101 ka1.wang.org
10.0.0.102 ka2.wang.org
[root@ka1 ~]#hostnamectl set-hostname ka1.wang.org
[root@ka1 ~]#apt install chrony
[root@ka1 ~]#chronyc sources
[root@ka1 ~]#apt install keepalived
##默认没有配置文件无法启动
[root@ka1 ~]#systemctl status keepalived.service
#利用范例生成配置文件
[root@ka1 ~]#dpkg -L keepalived
[root@ka1 ~]#cp /usr/share/doc/keepalived/samples/keepalived.conf.sample /etc/keepalived/
[root@ka1 ~]#cd /etc/keepalived/
[root@ka1 keepalived]#mv keepalived.conf.sample keepalived.conf
[root@ka1 keepalived]#vim keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_instance ka1 {
interface eth0
virtual_router_id 66
priority 100
advert_int 1
virtual_ipaddress {
10.0.0.66
}
}
[root@ka1 keepalived]#systemctl restart keepalived.service
[root@ka1 keepalived]#systemctl status keepalived.service
3-2、编译安装
3-2-1、安装依赖包
[root@ka2 ~]#apt -y install make gcc ipvsadm build-essential pkg-config automake autoconf libipset-dev libnl-3-dev libnl-genl-3-dev libssl-dev libxtables-dev libip4tc-dev libip6tc-dev libipset-dev libmagic-dev libsnmp-dev libglib2.0-dev libpcre2-dev libnftnl-dev libmnl-dev libsystemd-dev
#红帽系列依赖包
]# yum install gcc curl openssl-devel libnl3-devel net-snmp-devel
3-2-2、下载解压
[root@ka2 ~]#wget https://keepalived.org/software/keepalived-2.2.7.tar.gz
[root@ka2 ~]#tar xf keepalived-2.2.7.tar.gz -C /usr/local/src/
3-2-3、编译安装
[root@ka2 ~]#cd /usr/local/src/
[root@ka2 src]#cd keepalived-2.2.7
[root@ka2 keepalived-2.2.7]#./configure --prefix=/usr/local/keepalived --disable-fwmark
#选项--disable-fwmark 可用于禁用iptables规则,可防止VIP无法访问,无此选项默认会启用iptables规则
[root@ka2 keepalived-2.2.7]#make && make install
[root@ka2 keepalived-2.2.7]#cd
[root@ka2 ~]#/usr/local/keepalived/sbin/keepalived -v
Keepalived v2.2.7 (01/16,2022)
#自动生成keepalived.service文件
[root@ka2 ~]#ll /usr/lib/systemd/system/keepalived.service
-rw-r--r-- 1 root root 567 10月 26 19:56 /usr/lib/systemd/system/keepalived.service
#默认无法启动,缺少配置文件,需要拷贝自行创建
[root@ka2 ~]#mkdir /etc/keepalived
[root@ka2 ~]#cp /usr/local/src/keepalived-2.2.7/doc/samples/keepalived.conf.sample /etc/keepalived/keepalived.conf
[root@ka2 ~]#ll /etc/keepalived/keepalived.conf
-rw-r--r-- 1 root root 910 10月 26 20:05 /etc/keepalived/keepalived.conf
[root@ka2 ~]#systemctl restart keepalived.service
[root@ka2 ~]#systemctl status keepalived.service
4、KeepAlived 配置说明
4-1、 配置文件组成部分
/etc/keepalived/keepalived.conf
配置文件组成
- GLOBAL CONFIGURATION Global definitions:定义邮件配置,route_id,vrrp配置,多播地址等
- VRRP CONFIGURATION VRRP instance(s):定义每个vrrp虚拟路由器
- LVS CONFIGURATION Virtual server group(s) Virtual server(s):LVS集群的VS和RS
man keepalived.conf
4-2、全局配置
#/etc/keepalived/keepalived.conf
global_defs {
notification_email {
root@localhost #keepalived 发生故障切换时邮件发送的目标邮箱,可以按行区分写多个
[email protected]
}
notification_email_from keepalived@localhost #发邮件的地址
smtp_server 127.0.0.1 #邮件服务器地址
smtp_connect_timeout 30 #邮件服务器连接timeout
router_id ka1.wang.org #每个keepalived主机唯一标识,建议使用当前主机名,如果多节点重名可能会影响切换脚本执行
vrrp_skip_check_adv_addr #对所有通告报文都检查,会比较消耗性能,启用此配置后,如果收到的通告报文和上一个报文是同一个路由器,则跳过检查,默认值为全检查
vrrp_strict #严格遵守VRRP协议,启用此项后以下状况将无法启动服务:1.无VIP地址 2.配置了单播邻居 3.在VRRP版本2中有IPv6地址,开启动此项并且没有配置vrrp_iptables时会自动开启iptables防火墙规则,默认导致VIP无法访问,建议不加此项配置
vrrp_garp_interval 0 #gratuitous ARP messages 报文发送延迟,0表示不延迟
vrrp_gna_interval 0 #unsolicited NA messages (不请自来)消息发送延迟
vrrp_mcast_group4 224.0.0.18 #指定组播IP地址范围:224.0.0.0到239.255.255.255,默认值:224.0.0.18
vrrp_iptables #此项和vrrp_strict同时开启时,则不会添加防火墙规则,如果无配置vrrp_strict项,则无需启用此项配置,注意:新版加此项仍有iptables规则
}
4-3、配置虚拟路由器
vrrp_instance <STRING> { #<String>为vrrp的实例名,一般为业务名称配置参数
......
}
#配置参数:
state MASTER|BACKUP #当前节点在此虚拟路由器上的初始状态,状态为MASTER或者BACKUP
interface IFACE_NAME #绑定为当前虚拟路由器使用的物理接口,如:eth0,bond0,br0,可以和VIP不在一个网卡
virtual_router_id VRID #每个虚拟路由器唯一标识,范围:0-255,每个虚拟路由器此值必须唯一,否则服务无法启动,同属一个虚拟路由器的多个keepalived节点必须相同,务必要确认在同一网络中此值必须唯一
priority 100 #当前物理节点在此虚拟路由器的优先级,范围:1-254,每个keepalived主机节点此值不同
advert_int 1 #vrrp通告的时间间隔,默认1s
authentication { #认证机制
auth_type AH|PASS #AH为IPSEC认证(不推荐),PASS为简单密码(建议使用)
auth_pass <PASSWORD> #预共享密钥,仅前8位有效,同一个虚拟路由器的多个keepalived节点必须一样
}
virtual_ipaddress { #虚拟IP,生产环境可能指定几十上百个VIP地址
<IPADDR>/<MASK> brd <IPADDR> dev <STRING> scope <SCOPE> label <LABEL>
192.168.200.100 #指定VIP,不指定网卡,默认为eth0,注意:不指定/prefix,默认为/32
192.168.200.101/24 dev eth1 #指定VIP的网卡,建议和interface指令指定的网卡不在一个网卡
192.168.200.102/24 dev eth2 label eth2:1 # 指定VIP的网卡label
}
track_interface { #配置监控网络接口,一旦出现故障,则转为FAULT状态实现地址转移
eth0
eth1
...
}
4-4、启用 Keepalived 日志功能
[root@ka2 ~]#vim /usr/local/keepalived/etc/sysconfig/keepalived #编译安装路径
KEEPALIVED_OPTIONS="-D -S 6"
[root@ka2 ~]#vim /etc/rsyslog.d/keepalived.conf
local6.* /var/log/keepalived.log
[root@ka2 ~]#systemctl restart rsyslog.service keepalived.service
4-5、实现 Keepalived 独立子配置文件
当生产环境复杂时, /etc/keepalived/keepalived.conf 文件中保存所有集群的配置会导致内容过多,不易管理 可以将不同集群的配置,比如:不同集群的VIP配置放在独立的子配置文件中 利用include 指令可以实现包含子配置文件
格式:
include /path/file
[root@ka2 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka2.wang.org
}
include /etc/keepalived/conf.d/*.conf
[root@ka2 ~]#mkdir /etc/keepalived/conf.d
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka2.wang.org {
interface eth0
virtual_router_id 66
priority 80
advert_int 1
virtual_ipaddress {
10.0.0.66
}
}
[root@ka2 ~]#systemctl restart keepalived.service
5、Keepalived 实现 VRRP
5-1、实现master/slave的 Keepalived 单主架构
5-1-1、MASTER配置
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka1.wang.org {
state MASTER #在另一个结点上为BACKUP
interface eth0
virtual_router_id 66 #每个虚拟路由器必须唯一,同属一个虚拟路由器的多个keepalived节点必须相同
priority 100 #在另一个结点上为80(BACKUP优先级比master低)
advert_int 1
authentication { #预共享密钥认证,同一个虚拟路由器的keepalived节点必须一样
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
}
[root@ka1 ~]#systemctl restart keepalived.service
5-1-2、BACKUP配置
#配置文件和master基本一致,只需修改三行
[root@ka2 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka2.wang.org #id不一样
}
include /etc/keepalived/conf.d/*.conf
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka2.wang.org {
stats BACKUP #此处为backup
interface eth0
virtual_router_id 66
priority 80 #优先级低于master
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
}
5-1-3、脑裂
主备节点同时拥有VIP,此时为脑裂理象
注意:脑裂现象原因
- 心跳线故障
- 防火墙错误配置
- Keepalived 配置错误
5-2、 抢占模式和非抢占模式
5-2-1、非抢占模式 nopreempt
默认为抢占模式 preempt,即当高优先级的主机恢复在线后,会抢占低先级的主机的master角色,造成网络抖动,建议设置为非抢占模式 nopreempt ,即高优先级主机恢复后,并不会抢占低优先级主机的master 角色 注意: 非抢占模式下,如果原主机down机, VIP迁移至的新主机, 后续新主机也发生down时,VIP还会迁移回修复好的原主机 但如果新主机的服务down掉(keepalived服务正常),原主机也不会接管VIP,仍会由新主机拥有VIP即非抢占式模式,只是适合当主节点宕机,切换到从节点的一次性的高可用性,后续即使当原主节点修复好,仍无法再次起到高可用
注意:要关闭 VIP抢占,必须将各 Keepalived 服务器 state 配置为 BACKUP
#ka1:
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka1.wang.org {
state BACKUP #都为BACKUP
interface eth0
virtual_router_id 66
priority 100 #优先级高
nopreempt #添加此行,设为nopreempt
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
}
[root@ka1 ~]#systemctl restart keepalived.service
#ka2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka2.wang.org {
stats BACKUP #都为BACKUP
interface eth0
virtual_router_id 66
priority 80 #优先级低
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
}
#ka2,不需要配置nopreempt
#注意:如果ka2主机也是非抢占式,会导致ka1即使优先级降低于ka2,VIP也不会切换至ka2
5-3、抢占延迟模式 preempt_delay
抢占延迟模式,即优先级高的主机恢复后,不会立即抢回VIP,而是延迟一段时间(默认300s)再抢回VIP
preempt_delay # #指定抢占延迟时间为#s,默认延迟300s
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka1.wang.org {
state BACKUP
interface eth0
virtual_router_id 66
priority 100
# nopreempt
preempt_delay 60 #抢占延迟模式,默认延迟300s
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
}
5-4、VIP 单播配置
默认keepalived主机之间利用多播相互通告消息,会造成网络拥塞,可以替换成单播,减少网络流量
另外:有些公有云不支持多播,可以单播实现
注意:启用 vrrp_strict 时,不能启用单播
#在所有节点vrrp_instance语句块中设置对方主机的IP,建议设置为专用于对应心跳线网络的地址,而非使用业务网络
unicast_src_ip <IPADDR> #指定发送单播的源IP
unicast_peer {
<IPADDR> #指定接收单播的对方目标主机IP
......
}
#master
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
vrrp_mcast_group4 239.0.0.0 #单播优先于多播,多播配不配均可,如果不配,默认是224.0.0.18
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka1.wang.org {
state MASTER
interface eth0
virtual_router_id 66
priority 100
# nopreempt
preempt_delay 60
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101 #本机IP
unicast_peer { #指向对方主机IP
10.0.0.102 #如果有多个keepalived,再加其它节点的IP
# 10.0.0.103
}
}
#backup
[root@ka2 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka2.wang.org
vrrp_mcast_group4 239.0.0.0
}
include /etc/keepalived/conf.d/*.conf
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka2.wang.org {
stats BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
5-5、 Keepalived 通知脚本配置
当keepalived的状态变化时,可以自动触发脚本的执行,比如:发邮件通知用户 默认以用户keepalived_script身份执行脚本,如果此用户不存在,以root执行脚本
可以用下面指令指定脚本执行用户的身份
global_defs {
......
script_user <USER>
......
}
5-5-1、通知脚本类型
#当前节点成为主节点时触发的脚本
notify_master <STRING>|<QUOTED-STRING>
#当前节点转为备节点时触发的脚本
notify_backup <STRING>|<QUOTED-STRING>
#当前节点转为“失败”状态时触发的脚本
notify_fault <STRING>|<QUOTED-STRING>
#通用格式的通知触发机制,一个脚本可完成以上三种状态的转换时的通知
notify <STRING>|<QUOTED-STRING>
#当停止VRRP时触发的脚本
notify_stop <STRING>|<QUOTED-STRING>
5-5-2、脚本的调用方法
#在 vrrp_instance VI_1 语句块的末尾加下面行
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
[root@ka1 keepalived]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance ka1.wang.org {
state MASTER
interface eth0
virtual_router_id 66
priority 100
# nopreempt
preempt_delay 60
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
notify_master "/etc/keepalived/notify.sh master" #脚本路径
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
[root@ka1 keepalived]#chmod +x notify.sh
contact='[email protected]' #qq邮箱有问题,建议用163邮箱
email_send='[email protected]'
email_passwd='xenddddmynztddzbceb'
email_smtp_server='smtp.qq.com'
notify() {
if [[ $1 =~ ^(master|backup|fault)$ ]];then
mailsubject="$(hostname) to be $1, vip floating"
mailbody="$(date +'%F %T'): vrrp transition, $(hostname) changed to be $1"
send_email "$contact" "$mailsubject" "$mailbody"
else
echo "Usage: $(basename $0) {master|backup|fault}"
exit 1
fi
}
notify $1
#模拟master故障
[root@ka1 keepalived]#killall keepalived
#邮箱收到邮件:
2022-10-26 21:41:33: vrrp transition, ka2.wang.org changed to be master
5-6、实现 Master/Master 的 Keepalived 双主架构
master/slave的单主架构,同一时间只有一个Keepalived对外提供服务,此主机繁忙,而另一台主机却很空闲,利用率低下,可以使用master/master的双主架构,解决此问题。 Master/Master 的双主架构: 即将两个或以上VIP分别运行在不同的keepalived服务器,以实现服务器并行提供web访问的目的,提高服务器资源利用率
#ka1:
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
vrrp_instance VI_2 { #添加 VI_2 实例
state BACKUP
interface eth0
virtual_router_id 88
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:2
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
[root@ka1 ~]#systemctl restart keepalived.service
[root@ka1 ~]#hostname -I
10.0.0.101 10.0.0.66
#ka2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
stats BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
vrrp_instance VI_2 {
state MASTER
interface eth0
virtual_router_id 88
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:2
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
[root@ka2 ~]#systemctl restart keepalived.service
[root@ka2 ~]#hostname -I
10.0.0.102 10.0.0.88
5-7、三个节点的三主三从架构实现
#ka1:
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 99
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.99/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.103
}
}
[root@ka1 ~]#systemctl restart keepalived.service
#ka2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
stats MASTER
interface eth0
virtual_router_id 88
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.103
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
[root@ka2 ~]#systemctl restart keepalived.service
#ka3:
[root@ka3 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
stats MASTER
interface eth0
virtual_router_id 99
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.99/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.103
unicast_peer {
10.0.0.101
}
}
vrrp_instance VI_2 {
stats BACKUP
interface eth0
virtual_router_id 88
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.103
unicast_peer {
10.0.0.102
}
}
[root@ka3 ~]#systemctl restart keepalived.service
#测试
[root@ka1 ~]#systemctl stop keepalived.service
[root@ka2 ~]#hostname -I
10.0.0.102 10.0.0.88 10.0.0.66
[root@ka1 ~]#systemctl start keepalived.service
[root@ka1 ~]#hostname -I
10.0.0.101 10.0.0.66
[root@ka2 ~]#systemctl stop keepalived.service
[root@ka3 ~]#hostname -I
10.0.0.103 10.0.0.99 10.0.0.88
[root@ka3 ~]#systemctl stop keepalived.service
[root@ka1 ~]#hostname -I
10.0.0.101 10.0.0.66 10.0.0.99
5-8、三个节点的三主六从架构实现
#ka1:
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
10.0.0.103
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 88
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
10.0.0.103
}
}
vrrp_instance VI_3 {
state BACKUP
interface eth0
virtual_router_id 99
priority 60
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.99/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
10.0.0.103
}
}
[root@ka1 ~]#systemctl restart keepalived.service
[root@ka1 ~]#hostname -I
10.0.0.101 10.0.0.66
#ka2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
stats MASTER
interface eth0
virtual_router_id 88
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
10.0.0.103
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 99
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.99/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
10.0.0.103
}
}
vrrp_instance VI_3 {
state BACKUP
interface eth0
virtual_router_id 66
priority 60
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
10.0.0.103
}
}
[root@ka2 ~]#systemctl restart keepalived.service
[root@ka2 ~]#hostname -I
10.0.0.102 10.0.0.88
#ka3:
[root@ka3 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
stats MASTER
interface eth0
virtual_router_id 99
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.99/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.103
unicast_peer {
10.0.0.101
10.0.0.102
}
}
vrrp_instance VI_2 {
stats BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.103
unicast_peer {
10.0.0.102
10.0.0.101
}
}
vrrp_instance VI_3 {
stats BACKUP
interface eth0
virtual_router_id 88
priority 60
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.103
unicast_peer {
10.0.0.102
10.0.0.101
}
}
[root@ka3 ~]#systemctl restart keepalived.service
[root@ka3 ~]#hostname -I
10.0.0.103 10.0.0.99
#测试:
[root@ka1 ~]#systemctl stop keepalived.service
[root@ka3 ~]#hostname -I
10.0.0.103 10.0.0.99 10.0.0.66
[root@ka2 ~]#systemctl stop keepalived.service
[root@ka3 ~]#hostname -I
10.0.0.103 10.0.0.99 10.0.0.66 10.0.0.88
5-9、同步组
LVS NAT 模型VIP和DIP需要同步,需要同步组
vrrp_sync_group VG_1 {
group {
VI_1 # name of vrrp_instance (below)
VI_2 # One for each moveable IP
}
}
vrrp_instance VI_1 {
eth0
vip
}
vrrp_instance VI_2 {
eth1
dip
}
6、实现 IPVS 的高可用性
6-1、虚拟服务器配置结构
每一个虚拟服务器即一个IPVS集群 可以通过下面语法实现
virtual_server IP port {
...
real_server {
...
}
real_server {
...
}
...
}
6-2、Virtual Server (虚拟服务器)的定义格式
virtual_server IP port #定义虚拟主机IP地址及其端口
virtual_server fwmark int #ipvs的防火墙打标,实现基于防火墙的负载均衡集群
virtual_server group string #使用虚拟服务器组
6-3、虚拟服务器组
将多个虚拟服务器定义成一个组,统一对外服务,如:http和https定义成一个虚拟服务器组
#参考文档:/usr/share/doc/keepalived/keepalived.conf.virtual_server_group
virtual_server_group <STRING> {
# Virtual IP Address and Port
<IPADDR> <PORT>
<IPADDR> <PORT>
...
# <IPADDR RANGE> has the form
# XXX.YYY.ZZZ.WWW-VVV eg 192.168.200.1-10
# range includes both .1 and .10 address
<IPADDR RANGE> <PORT># VIP range VPORT
<IPADDR RANGE> <PORT>
...
# Firewall Mark (fwmark)
fwmark <INTEGER>
fwmark <INTEGER>
...
}
6-4、虚拟服务器配置
virtual_server IP port { #VIP和PORT
delay_loop <INT> #检查后端服务器的时间间隔
lb_algo rr|wrr|lc|wlc|lblc|sh|dh #定义调度方法
lb_kind NAT|DR|TUN #集群的类型,注意要大写
persistence_timeout <INT> #持久连接时长
protocol TCP|UDP|SCTP #指定服务协议,一般为TCP
sorry_server <IPADDR> <PORT> #所有RS故障时,备用服务器地址
real_server <IPADDR> <PORT> { #RS的IP和PORT
weight <INT> #RS权重
notify_up <STRING>|<QUOTED-STRING> #RS上线通知脚本
notify_down <STRING>|<QUOTED-STRING> #RS下线通知脚本
HTTP_GET|SSL_GET|TCP_CHECK|SMTP_CHECK|MISC_CHECK { ... } #定义当前主机健康状态检测方法
}
}
#注意:括号必须分行写,两个括号写在同一行,如: }} 会出错
6-5、应用层监测
应用层检测:HTTP_GET|SSL_GET
HTTP_GET|SSL_GET {
url {
path <URL_PATH> #定义要监控的URL
status_code <INT> #判断上述检测机制为健康状态的响应码,一般为 200
}
connect_timeout <INTEGER> #客户端请求的超时时长, 相当于haproxy的timeout server
nb_get_retry <INT> #重试次数
delay_before_retry <INT> #重试之前的延迟时长
connect_ip <IP ADDRESS> #向当前RS哪个IP地址发起健康状态检测请求
connect_port <PORT> #向当前RS的哪个PORT发起健康状态检测请求
bindto <IP ADDRESS> #向当前RS发出健康状态检测请求时使用的源地址
bind_port <PORT> #向当前RS发出健康状态检测请求时使用的源端口
}
virtual_server 10.0.0.66 80 {
lb_algo rr
lb_kind DR
protocol TCP
sorry_server 127.0.0.1 80
real_server 10.0.0.28 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.38 80 {
weight 1
HTTP_GET {
uri {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
}
6-6、TCP监测
传输层检测:TCP_CHECK
TCP_CHECK {
connect_ip <IP ADDRESS> #向当前RS的哪个IP地址发起健康状态检测请求
connect_port <PORT> #向当前RS的哪个PORT发起健康状态检测请求
bindto <IP ADDRESS> #发出健康状态检测请求时使用的源地址
bind_port <PORT> #发出健康状态检测请求时使用的源端口
connect_timeout <INTEGER> #客户端请求的超时时长, 等于haproxy的timeout server
}
virtual_server 10.0.0.66 80 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.28 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
real_server 10.0.0.38 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
6-7、实现单主的 LVS-DR 模式
6-7-1、准备web服务器并使用脚本绑定VIP至web服务器lo网卡
#两台web服务器执行:
[root@rocky8 ~]#cat lvs_dr_rs.sh
#!/bin/bash
vip=10.0.0.66
mask='255.255.255.255'
dev=lo:1
#rpm -q httpd &> /dev/null || yum -y install httpd &>/dev/null
#service httpd start &> /dev/null && echo "The httpd Server is Ready!"
#echo "`hostname -I`" > /var/www/html/index.html
case $1 in
start)
echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore
echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce
ifconfig $dev $vip netmask $mask #broadcast $vip up
#route add -host $vip dev $dev
echo "The RS Server is Ready!"
;;
stop)
ifconfig $dev down
echo 0 > /proc/sys/net/ipv4/conf/all/arp_ignore
echo 0 > /proc/sys/net/ipv4/conf/lo/arp_ignore
echo 0 > /proc/sys/net/ipv4/conf/all/arp_announce
echo 0 > /proc/sys/net/ipv4/conf/lo/arp_announce
echo "The RS Server is Canceled!"
;;
*)
echo "Usage: $(basename $0) start|stop"
exit 1
;;
esac
[root@rocky8 ~]#bash lvs_dr_rs.sh start
#ka1:
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
virtual_server 10.0.0.66 80 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.28 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.38 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
#ka2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
virtual_server 10.0.0.66 80 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.28 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.38 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
6-7-2、实现双主的 LVS-DR 模式
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 88
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:2
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
virtual_server 10.0.0.66 80 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.28 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.38 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
virtual_server 10.0.0.88 80 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.48 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.58 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
#ka2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:1
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
vrrp_instance VI_2{
state BACKUP
interface eth0
virtual_router_id 88
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:2
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
virtual_server 10.0.0.66 80 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.28 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.38 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
virtual_server 10.0.0.88 {
delay_loop 6
lb_algo rr
lb_kind DR
protocol TCP
# persistence_timeout 1230
sorry_server 127.0.0.1 80
real_server 10.0.0.48 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.58 80 {
weight 1
TCP_CHECK {
connect_timeout 5
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
6-8、双主分别实现httpd和mysql服务的调度
#keepalived1:
[root@ka1 ~]#vim /etc/keepalived/conf.d/web.conf
vrrp_instance web1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_TYPE pass
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:66
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
[root@ka1 ~]#vim /etc/keepalived/conf.d/lvs_web.conf
virtual_server 10.0.0.66 80 {
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
sorry server 10.0.0.28 80
real_server 10.0.0.48 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.58 80 {
weight 1
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
=============================================================================
[root@ka1 ~]#vim /etc/keepalived/conf.d/mysql.conf
vrrp_instance mysql {
state BACKUP
interface eth0
virtual_router_id 88
priority 80
advert_int 1
authentication {
auth_TYPE pass
auth_PASS 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:2
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
[root@ka1 ~]#vim /etc/keepalived/conf.d/lvs_mysql.conf
virtual_server 10.0.0.88 3306 {
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
real_server 10.0.0.48 3306 {
weight 1
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
real_server 10.0.0.58 3306 {
weight 1
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}
[root@ka1 ~]#systemctl restart keepalived.service
[root@ka1 ~]#hostname -I
10.0.0.101 10.0.0.66
#keepalived2:
[root@ka2 ~]#vim /etc/keepalived/conf.d/web.conf
vrrp_instance web1 {
state BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_TYPE pass
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:66
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
[root@ka2 ~]#vim /etc/keepalived/conf.d/lvs_web.conf
virtual_server 10.0.0.66 80 {
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
sorry server 10.0.0.28 80
real_server 10.0.0.48 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.58 80 {
weight 1
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
=============================================================================
[root@ka2 ~]#vim /etc/keepalived/conf.d/mysql.conf
vrrp_instance mysql {
state MASTER
interface eth0
virtual_router_id 88
priority 100
advert_int 1
authentication {
auth_TYPE pass
auth_PASS 123456
}
virtual_ipaddress {
10.0.0.88/24 dev eth0 label eth0:2
}
unicast_src_ip 10.0.0.102
unicast_peer {
10.0.0.101
}
}
[root@ka2 ~]#vim /etc/keepalived/conf.d/lvs_mysql.conf
virtual_server 10.0.0.88 3306 {
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
real_server 10.0.0.48 3306 {
weight 1
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
real_server 10.0.0.58 3306 {
weight 1
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}
[root@ka2 ~]#systemctl restart keepalived.service
[root@ka2 ~]#hostname -I
10.0.0.102 10.0.0.88
#测试:
[root@ka3 ~]#while true; do mysql -utest -p123456 -h10.0.0.88 -e 'select @@hostname';curl 10.0.0.66;sleep 1;done
mysql: [Warning] Using a password on the command line interface can be insecure.
+------------------+
| @@hostname |
+------------------+
| mysql48.wang.org |
+------------------+
10.0.0.48
mysql: [Warning] Using a password on the command line interface can be insecure.
+------------------+
| @@hostname |
+------------------+
| mysql58.wang.org |
+------------------+
10.0.0.58
mysql: [Warning] Using a password on the command line interface can be insecure.
+------------------+
| @@hostname |
+------------------+
| mysql48.wang.org |
+------------------+
10.0.0.48
mysql: [Warning] Using a password on the command line interface can be insecure.
+------------------+
| @@hostname |
+------------------+
| mysql58.wang.org |
+------------------+
10.0.0.58
6-9、实现单主的 LVS-DR 模式,利用FWM绑定成多个服务为一个集群服务
#两个keepalived节点都执行(10.0.0.101、10.0.0.102):
[root@ka1 ~]#iptables -t mangle -A PREROUTING -d 10.0.0.66 -p tcp -m multiport --dports 80,443 -j MARK --set-mark 6
[root@ka1 ~]#vim /etc/keepalived/conf.d/web.conf
vrrp_instance web1 {
state MASTER #在另一个节点为BACKUP
interface eth0
virtual_router_id 66
priority 100 #在另一个节点为80
advert_int 1
authentication {
auth_TYPE pass
auth_pass 123456
}
virtual_ipaddress {
10.0.0.66/24 dev eth0 label eth0:66
}
unicast_src_ip 10.0.0.101 #另一个节点源地址是102
unicast_peer {
10.0.0.102 #另一个节点是101
}
track_interface {
eth0
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
[root@ka1 ~]#vim /etc/keepalived/conf.d/fwmark_web.conf
virtual_server fwmark 6 { #fwmark 6 和iptables定义的名称一样
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
sorry server 127.0.0.1 80
real_server 10.0.0.48 80 { #注意端口必须指定,只用于健康性检查,而非通信
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.0.0.58 80 {
weight 1
HTTP_GET {
url {
path /monitor.html
status_code 200
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
[root@ka1 ~]#systemctl restart keepalived.service
#web服务器(10.0.0.48、10.0.0.58):
[root@mysql48 ~]# bash lvs_dr_rs.sh start
#制作ssl证书,并且开启nginx443端口
[root@mysql48 ~]# ls /etc/nginx/conf.d/certs/
ca.crt ca.srl www.wang.org.crt www.wang.org.key
ca.key certs.sh www.wang.org.csr www.wang.org.pem
#测试访问:
[root@ka3 ~]#curl -k https://10.0.0.66
10.0.0.48
[root@ka3 ~]#curl -k https://10.0.0.66
10.0.0.58
[root@ka3 ~]#curl 10.0.0.66
10.0.0.48
[root@ka3 ~]#curl 10.0.0.66
10.0.0.58
7、基于 VRRP Script 实现其它应用的高可用性
keepalived利用 VRRP Script 技术,可以调用外部的辅助脚本进行资源监控,并根据监控的结果实现优先动态调整,从而实现其它应用的高可用性功能
参考配置文件:
/usr/share/doc/keepalived/keepalived.conf.vrrp.localcheck
7-1、 VRRP Script 配置
分两步实现:
- 定义脚本 vrrp_script:自定义资源监控脚本,vrrp实例根据脚本返回值,公共定义,可被多个实例调用,定义在vrrp实例之外的独立配置块,一般放在global_defs设置块之后,是和global_defs平级的语句块 通常此脚本用于监控指定应用的状态。一旦发现应用的状态异常,则触发对MASTER节点的权重减至低于SLAVE节点,从而实现 VIP 切换到 SLAVE 节点 当 keepalived_script 用户存在时,会以此用户身份运行脚本,否则默认以root运行脚本 注意: 此定义脚本的语句块一定要放在下面调用此语句vrrp_instance语句块的前面
vrrp_script <SCRIPT_NAME> {
script <STRING>|<QUOTED-STRING> #此脚本返回值为非0时,会触发下面OPTIONS执行
OPTIONS
}
- 调用脚本 track_script:调用vrrp_script定义的脚本去监控资源,定义在VRRP实例之内,调用事先定义的vrrp_script
track_script {
SCRIPT_NAME_1
SCRIPT_NAME_2
}
7-1-1、定义 VRRP script
vrrp_script <SCRIPT_NAME> { #定义一个检测脚本,在global_defs 之外配置
script <STRING>|<QUOTED-STRING> #shell命令或脚本路径
interval <INTEGER> #间隔时间,单位为秒,默认1秒
timeout <INTEGER> #超时时间
weight <INTEGER:-254..254> #默认为0,如果设置此值为负数,当上面脚本返回值为非0时,会将此值与本节点权重相加可以降低本节点权重,即表示fall. 如果是正数,当脚本返回值为0,会将此值与本节点权重相加可以提高本节点权重,即表示 rise.通常使用负值
fall <INTEGER> #执行脚本连续几次都失败,则转换为失败,建议设为2以上
rise <INTEGER> #执行脚本连续几次都成功,把服务器从失败标记为成功
user USERNAME [GROUPNAME] #执行监测脚本的用户或组
init_fail #设置默认标记为失败状态,监测成功之后再转换为成功状态
}
7-1-2、调用 VRRP script
vrrp_instance VI_1 {
...
track_script {
<SCRIPT_NAME>
}
}
7-2、利用脚本实现主从角色切换
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_script check_down {
script "[ ! -f /etc/keepalived/down ] " #/etc/keepalived/down存在时返回非0,触发权重-30
interval 1
weight -30
fall 3
rise 2
timeout 2
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 33
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.33/24 dev eth0 label eth0:1
}
track_interface {
eth0
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
track_script {
check_down #调用前面定义的脚本
}
}
#测试
[root@ka1 ~]#touch /etc/keepalived/down
[root@ka3 ~]#tcpdump -i eth0 -nn host 224.0.0.18
6:04:07.101894 IP 10.0.0.101 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 70, authtype simple, intvl 1s, length 20
16:04:08.103307 IP 10.0.0.101 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 70, authtype simple, intvl 1s, length 20
16:04:08.788557 IP 10.0.0.102 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 80, authtype simple, intvl 1s, length 20
16:04:09.790807 IP 10.0.0.102 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 80, authtype simple, intvl 1s, length 20
16:04:10.792118 IP 10.0.0.102 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 80, authtype simple,
[root@ka1 ~]#rm -f /etc/keepalived/down
[root@ka3 ~]#tcpdump -i eth0 -nn host 224.0.0.18
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
16:05:38.489491 IP 10.0.0.101 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 100, authtype simple, intvl 1s, length 20
16:05:39.490135 IP 10.0.0.101 > 224.0.0.18: VRRPv2, Advertisement, vrid 33, prio 100, authtype simple, intvl 1s, length 20
7-3、实现单主模式的 Nginx 反向代理的高可用
#在两个节点都配置nginx反向代理
[root@ka1 ~]#vim /etc/nginx/conf.d/www.li.org.conf
upstream li {
server 10.0.0.28:80 weight=1;
server 10.0.0.38:80 weight=1;
}
server {
listen 80;
server_name www.li.org;
location / {
proxy_pass http://li;
}
}
#keepalived节点都执行
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_script check_down {
script "/etc/keepalived/check_nginx.sh"
interval 1
weight -30
fall 3
rise 2
timeout 2
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.li.org.conf
vrrp_instance VI_1 {
state MASTER #在另一个节点为BACKUP
interface eth0
virtual_router_id 44
priority 100 #在另一个节点为80
advert_int 1
authentication {
auth_TYPE pass
auth_pass 123456
}
virtual_ipaddress {
10.0.0.44/24 dev eth0 label eth0:4
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
track_script {
check_nginx
}
unicast_src_ip 10.0.0.101 #另一节点102
unicast_peer {
10.0.0.102 #另一节点101
}
}
[root@ka1 ~]#vim /etc/keepalived/check_nginx.sh
/usr/bin/killall -0 nginx || systemctl restart nginx #自动重启服务
[root@ka1 ~]#chmod +x /etc/keepalived/check_nginx.sh
#测试
[root@ka1 keepalived]#systemctl stop nginx
[root@ka1 keepalived]#systemctl status nginx #自动重启服务
● nginx.service - A high performance web server and a reverse proxy server
Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2022-10-27 16:43:23 CST; 26s ago
7-4、实现双主模式 Nginx 反向代理的高可用
#在两个节点都配置nginx反向代理
[root@ka1 ~]#vim /etc/nginx/conf.d/www.li.org.conf
upstream li {
server 10.0.0.28:80 weight=1;
server 10.0.0.38:80 weight=1;
}
upstream wang {
server 10.0.0.48:80 weight=1;
server 10.0.0.58:80 weight=1;
}
server {
listen 80;
server_name www.li.org;
location / {
proxy_pass http://li;
}
}
server {
listen 80;
server_name www.wang.org;
location / {
proxy_pass http://wang;
}
}
# keepalived所有节点执行:
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_script check_nginx {
script "/etc/keepalived/check_nginx.sh"
interval 1
weight -30
fall 3
rise 2
timeout 2
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.li.org.conf
vrrp_instance VI_1 {
state MASTER #在另一个节点为BACKUP
interface eth0
virtual_router_id 44
priority 100 #在另一个节点为80
advert_int 1
authentication {
auth_TYPE pass
auth_pass 123456
}
virtual_ipaddress {
10.0.0.44/24 dev eth0 label eth0:4
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
track_script {
check_nginx
}
unicast_src_ip 10.0.0.101 #在另一个节点为102
unicast_peer {
10.0.0.102 #在另一个节点为101
}
}
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_2 {
state BACKUP #在另一个节点为MASTER
interface eth0
virtual_router_id 33
priority 80 #在另一个节点为100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.33/24 dev eth0 label eth0:1
}
track_interface {
eth0
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
track_script {
check_down
}
unicast_src_ip 10.0.0.101 #在另一个节点为102
unicast_peer {
10.0.0.102 #在另一个节点为101
}
track_script {
check_nginx
}
}
[root@ka1 ~]#systemctl restart keepalived.service
#测试:
[root@ka1 ~]#systemctl stop nginx
[root@ka1 ~]#systemctl status nginx
● nginx.service - A high performance web server and a reverse proxy server
Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2022-10-27 16:59:53 CST; 4s ago
[root@ka3 ~]#curl www.wang.org
10.0.0.48
[root@ka3 ~]#curl www.wang.org
10.0.0.58
[root@ka3 ~]#curl www.li.org
welcome to 8.222222
[root@ka3 ~]#curl www.li.org
welcome to 8.333333333
7-5、实现 HAProxy 高可用
#两个节点都配置haprxoy(10.0.0.101、10.0.0.102):
[root@ka1 ~]#vim /etc/haproxy/haproxy.cfg
listen wang_http
bind 10.0.0.33:80
server web1 10.0.0.48:80 check
server web2 10.0.0.58:80 check
listen li_http
bind 10.0.0.44:80
server web3 10.0.0.28:80 check
server web4 10.0.0.38:80 check
listen stats
mode http
bind 10.0.0.101:9999
stats enable
log global
stats uri /haproxy-status
stats auth admin:123456
#在两个ka1和ka2两个节点启用内核参数
[root@ka1 ~]#vim /etc/sysctl.conf
net.ipv4.ip_nonlocal_bind = 1
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_script check_haproxy {
script "/etc/keepalived/check_haproxy.sh"
interval 1
weight -30
fall 3
rise 2
timeout 2
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.li.org.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 44
priority 100
advert_int 1
authentication {
auth_TYPE pass
auth_pass 123456
}
virtual_ipaddress {
10.0.0.44/24 dev eth0 label eth0:4
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
track_script {
check_haproxy
}
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
}
[root@ka1 ~]#vim /etc/keepalived/conf.d/www.wang.org.conf
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 33
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.33/24 dev eth0 label eth0:1
}
track_interface {
eth0
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
unicast_src_ip 10.0.0.101
unicast_peer {
10.0.0.102
}
track_script {
check_haproxy
}
}
7-6、实现 MySQL 双主模式的高可用
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_script check_mysql {
script "/etc/keepalived/check_mysql.sh" #只需在第一个节点上实现脚本
interval 1
weight -30
fall 3
rise 2
timeout 2
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/mysql.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 55
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.6/24 dev eth0 label eth0:6
}
track_interface {
eth0
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
track_script {
check_mysql #只需在第一个节点上实现脚本
}
}
[root@ka1 ~]#vim /etc/keepalived/check_mysql.sh
slave_is=( $(mysql -uadmin -p123456 -h10.0.0.102 -e "show slave status\G" | grep "Slave_.*_Running:" | awk 'print $2') )
if [ "${slave_is[0]}" = "Yes" -a "${slave_is[1]}" = "Yes" ];then
exit 0
else
exit 1
fi
7-7、实现 Zabbix Server 的高可用
#keepalived所有节点执行(10.0.0.101、10.0.0.102):
[root@ka1 ~]#bash install_zabbix_server5.0.sh #脚本详见:https://blog.51cto.com/dayu/5801993
#Zabbix Server 使用下面相同的配置
[root@ka1 ~]#vim /etc/zabbix/zabbix_server.conf
SourceIP=10.0.0.77
[root@ka1 ~]#systemctl restart zabbix-server.service
#keepalived相关配置
#指定检测脚本
[root@ka1 ~]#vim /etc/keepalived/keepalived.conf
global_defs {
router_id ka1.wang.org
}
vrrp_script check_zabbix_server {
script "/usr/bin/killall -0 zabbix-server"
interval 1
weight -30
fall 3
rise 2
timeout 2
}
include /etc/keepalived/conf.d/*.conf
[root@ka1 ~]#vim /etc/keepalived/conf.d/zabbix.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 66
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.77/24 dev eth0 label eth0:7
}
notify_master "systemctl start zabbix-server"
notify_backup "systemctl stop zabbix-server"
track_script {
check_zabbix_server
}
}
[root@ka1 ~]#systemctl restart keepalived.service
#keepalived2:(10.0.0.102)
[root@ka2 ~]#vim /etc/keepalived/conf.d/zabbix.conf
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 66
priority 80
advert_int 1
authentication {
auth_type PASS
auth_pass 123456
}
virtual_ipaddress {
10.0.0.77/24 dev eth0 label eth0:7
}
notify_master "systemctl start zabbix-server"
notify_backup "systemctl stop zabbix-server"
}
#注意:脚本check_zabbix_server 在ka2节点不能启用,否则会导致ka2节点也降低优先级,从而切换失败
[root@ka2 ~]#systemctl restart keepalived.service
总结:
1、实例名称不能一样;标签:10.0,可用,keepalived,etc,conf,root,eth0 From: https://blog.51cto.com/dayu/5801998
2、state 后边的master,backup不能一样
3、同一虚拟路由id要一样
4、优先级不能一样
5、尽量不要用组播,如果有多个实例一定要用单播,要不然会有不轮询或者vip飘不过去的问题