写在前面
- 今天和小伙伴们分享一些 Keepalived 相关笔记
- 博文内容涉及：
- vrrp 协议由来
- Ansible 方式 Keepalived安装部署
- Keepalived 脚本方式配置服务检查
- Keepalived 自动化部署 Ansible 角色编写
- 食用方式：
- 需要 Linux、Ansible 基础知识
- 理解不足小伙伴帮忙指正
「 勿忘国耻，铭记历史」
官网帮助文档：https://www.keepalived.org/manpage.html
「关于keepalived是什么，在官网中这样描述」：
Keepalived 是一个用 C 语言编写的路由软件。该项目的主要目标是为 Linux 系统和基于 Linux 的基础架构提供简单而强大的负载平衡和高可用性设施。
负载平衡框架依赖于众所周知且广泛使用的Linux 虚拟服务器 (IPVS) 内核模块，提供第 4 层负载平衡。Keepalived 实现了一组检查器，以根据其健康状况动态和自适应地维护和管理负载平衡的服务器池。(本文不涉及)
高可用性是通过 VRRP实现的协议。VRRP 是路由器故障转移的基础。此外，Keepalived 实现了一组与 VRRP 有限状态机的挂钩，提供低级和高速协议交互。为了提供最快的网络故障检测，Keepalived 实现了BFD协议。VRRP 状态转换可以考虑 BFD 提示来驱动快速状态转换。Keepalived 框架可以单独使用，也可以一起使用，以提供弹性基础架构
「Keepalived 是免费软件；您可以根据自由软件基金会发布的 GNU 通用公共许可条款重新分发和/或修改它；许可证的第 2 版，或（由您选择）任何更高版本。」
今天和小伙伴分享的主要是高可用热备部署，关于负载均衡方面的之后和小伙伴们分享，在部署keepalived之前，需要了解下VRRP协议
vrrp协议由来
当网关路由器出现故障时，本网段内以该设备为网关的主机都不能与 Internet 进行通信。所以需要进行容灾处理，但是通过部署多网关的方式实现网关的备份,存在一些问题:网关间IP地址冲突；主机会频繁切换网络出口。所以为解决网关路由的单点故障，有了VRRP协议。
VRRP即虚拟路由冗余协议,VRRP能够在不改变组网的情况下，从多台网关设备里产生一个虚拟路由器，通过配置虚拟路由器的IP地址为默认网关，实现网关的备份。
对外提供网关服务的是这个虚拟路由器。这样不管是真实路由器哪个出现问题，都不会影响整个网络的运行，提高了网络结构的稳定性。
路由器VRRP配置方式
- 配置VRRP的成员；
- 配置VRRP的优先级 (默认100)；
- 查看VRRP信息
VRRP协议通过一种竞选机制来将路由任务交给某个vrrp路由器的。
在VRRP物理结构中，有多个物理的VRRP路由器，其中有一台称为“master”（主节点路由器），其他的都是“backup”（备节点路由器）
在VRRP虚拟结构中，虚拟路由都是通过MAC VRID的形式来标识的，如54-89-98-6F-3D-B5-{vrid}只有master节点才会发送VRRP包（vrrp advertisement message）当master节点宕掉的时候，backup中优先级最高的VRRP设备会抢占并升级为master
下面为配置的简单Demo
三层交换机SW1上配置, 主路由器(Master)
#三层交换机SW1上配置, 主路由器(Master)
<Huawei>system-view #进入系统视图
[Huawei]sysname SW1 #修改设备名字
[SW1]
[SW1]undo info-center enable #取消信息提示
#给vlan1配置网关
[SW1]interface Vlanif 1
[SW1-Vlanif1]ip address 192.168.1.252 255.255.255.0
#将三层交换机SW1配置为VRRP的成员，设置虚拟IP地址
[SW1-Vlanif1]vrrp vrid 1 virtual-ip 192.168.1.254
#配置VRRP的优先级，不写默认为100
[SW1-Vlanif1]vrrp vrid 1 priority 105
[SW1-Vlanif1]
#查看VRRP配置信息
[SW1-Vlanif1]display vrrp brief
三层交换机SW2上配置,,备用路由器(backup)
#三层交换机SW2上配置,,备用路由器(backup)
<Huawei>system-view #进入系统视图
[Huawei]sysname SW2 #修改设备名字
[SW2]
[SW2]undo info-center enable #取消信息提示
#给vlan1配置网关
[SW2]interface Vlanif 1
[SW2-Vlanif1]ip address 192.168.1.253 255.255.255.0
#将三层交换机SW1配置为VRRP的成员，设置虚拟IP地址
[SW2-Vlanif1]vrrp vrid 1 virtual-ip 192.168.1.254
#不用设置优先级，默认为100
#查看VRRP配置信息
[SW2-Vlanif1]display vrrp brief
keepalived 安装部署
回到keepalived中，keepalived 通过VRRP（Virtual Router Redundancy Protocol）虚拟路由冗余协议来实现故障转移。keepalived正常工作时，主节点（master）会不断的发送心跳信息给备节点（backup）
代码语言：javascript复制┌──[root@vms153.liruilongs.github.io]-[~]
└─$tcpdump -i ens32 -nn host 224.0.0.18 #组播地址
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on ens32, link-type EN10MB (Ethernet), capture size 262144 bytes
23:27:36.149062 IP 192.168.26.153 > 224.0.0.18: VRRPv2, Advertisement, vrid 51, prio 100, authtype simple, intvl 1s, length 20
23:27:37.150969 IP 192.168.26.153 > 224.0.0.18: VRRPv2, Advertisement, vrid 51, prio 100, authtype simple, intvl 1s, length 20
23:27:38.152021 IP 192.168.26.153 > 224.0.0.18: VRRPv2, Advertisement, vrid 51, prio 100, authtype simple, intvl 1s, length 20
^C
3 packets captured
3 packets received by filter
0 packets dropped by kernel
┌──[root@vms153.liruilongs.github.io]-[~]
└─$
当备节点在一定时间内没有收到主节点的心跳信息时，备节点会认为主节点宕了，就会接管主节点上的资源，并继续向外提供服务保证其可用性,当主节点恢复时，备节点会自动让出资源并再次自动成为备节点
这里我们通过 ansible 安装配置，下面的两台机器为我们要配置的机器，也就是node组，在master节点操作
- 192.168.26.153
- 192.168.26.154
┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat inventory
[master]
192.168.26.152
[node]
192.168.26.153
192.168.26.154
安装web服务测试用
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible node -m shell -a "yum -y install httpd"
编写一个小剧本用于环境初始化，这个剧本实现对httpd服务的欢迎页进行内容填充，重启服务，设置防火墙域为trusted，即没有规则
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat httpd.yaml
---
- name: httpd init
hosts: node
tasks:
- name: httpd content
shell: "echo `hostname` > /var/www/html/index.html"
- name: Restart service httpd, in all cases
service:
name: httpd
state: restarted
- name: firewall
shell: firewall-cmd --set-default-zone=trusted
┌──[root@vms152.liruilongs.github.io]-[~]
└─$
执行剧本并测试填充结果测试
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible-playbook httpd.yaml
........
┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible node -m shell -a 'hostname;cat /var/www/html/index.html'
192.168.26.154 | CHANGED | rc=0 >>
vms154.liruilongs.github.io
vms154.liruilongs.github.io
192.168.26.153 | CHANGED | rc=0 >>
vms153.liruilongs.github.io
vms153.liruilongs.github.io
安装 keepalived，我们使用的版本为：keepalived-1.3.5-19.el7.x86_64
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible node -m yum -a 'name=keepalived state=installed'
192.168.26.154 | SUCCESS => {
。。。。。。
编辑配置文件模板，把主备节点配置文件中不一样的，或者希望单独设置的内容做成变量
┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat keepalived.conf.j2
! Configuration File for keepalived
global_defs {
router_id LVS_DEVEL #设置路由ID,可以和主机名相同，也可以随便定义
vrrp_iptables #手动添加(禁止设置防火墙规则，keepalved每次启动都会自动添加防火墙拒绝所有的规则)
}
vrrp_instance VI_1 {
state {{ role }}
interface ens32 #定义网络接口，根据自己虚拟机上的网卡修改
virtual_router_id 51 #主备服务器VRID号必须保持一致
priority {{ priority }} #服务器优先级，优先级高则优先获得浮动IP
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.26.200
}
}
编写剧本，复制模板文件，然后重启keepalived服务，这里我们通过两个小剧本的方式传递不同的变量
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat keepalived.yaml
---
- name: vms153.liruilongs.github.io config
hosts: 192.168.26.153
tags:
- master
vars:
role: MASTER
priority: 100
tasks:
- name: copy keeplived config
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
- name: restart keeplived
service:
name: keepalived
state: restarted
- name: vms154.liruilongs.github.io config
hosts: 192.168.26.154
tags:
- backup
vars:
role: BACKUP
priority: 50
tasks:
- name: copy keepalived config
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
- name: restart keepalived
service:
name: keepalived
state: restarted
运行剧本并测试
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible-playbook keepalived.yaml
。。。。。。。。。。。
假设153机器应为某些原因，需要进行停机处理，我们可以直接把 keepalived 干掉,vip自动切到154
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$curl 192.168.26.200:80
vms153.liruilongs.github.io
┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible 192.168.26.153 -m shell -a "systemctl stop keepalived"
192.168.26.153 | CHANGED | rc=0 >>
┌──[root@vms152.liruilongs.github.io]-[~]
└─$curl 192.168.26.200:80
vms154.liruilongs.github.io
┌──[root@vms152.liruilongs.github.io]-[~]
└─$
如果这个时候153机器恢复，那么我们可以重新拉起keepalived服务，vip回到153
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible 192.168.26.153 -m shell -a "systemctl start keepalived"
192.168.26.153 | CHANGED | rc=0 >>
┌──[root@vms152.liruilongs.github.io]-[~]
└─$curl 192.168.26.200:80
vms153.liruilongs.github.io
上面的操作，我们可以整合到一个剧本里
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat keepalived.yaml
---
- name: keepalived init
hosts: node
tasks:
- name: install
yum:
name:
- httpd
- keepalived
state: installed
- name: httpd content
shell: "echo `hostname` > /var/www/html/index.html"
- name: Restarted httpd
service:
name: httpd
state: restarted
- name: firewall clons
shell: firewall-cmd --set-default-zone=trusted
# 主机配置
- name: vms153.liruilongs.github.io config
hosts: 192.168.26.153
tags:
- master
vars:
role: MASTER
priority: 100
vip: 192.168.26.200
interface: ens32
tasks:
- name: copy keeplived config
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
- name: restart keepalived
service:
name: keepalived
state: restarted
# 备机配置
- name: vms154.liruilongs.github.io config
hosts: 192.168.26.154
tags:
- backup
vars:
role: BACKUP
priority: 90
vip: 192.168.26.200
interface: ens32
tasks:
- name: copy keepalived config
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
- name: restart keepalived
service:
name: keepalived
state: restarted
对于配置文件也可以更灵活一点
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat keepalived.conf.j2
! Configuration File for keepalived
global_defs {
router_id LVS_DEVEL #设置路由ID,可以和主机名相同，也可以随便定义
vrrp_iptables #手动添加(禁止设置防火墙规则，keepalved每次启动都会自动添加防火墙拒绝所有的规则)
}
vrrp_instance VI_1 {
state {{ role }}
interface {{ interface }} #定义网络接口，根据自己虚拟机上的网卡修改
virtual_router_id 51 #主备服务器VRID号必须保持一致
priority {{ priority }} #服务器优先级，优先级高则优先获得浮动IP
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
{{ vip }}
}
}
有小伙伴会讲，这也太水了，每次故障都需要自己去进行主备切换，其实上面的配置为keepalived的最简单配置，没有使用keepalived 的检查配置，，告警等其他的功能。
如果是IPVS使用keepalived，可以对后端RealServer进行健康状况检查，支持网络层、传输层、应用层进行健康检查。
配置文件解析
熟悉下配置文件，keepalived的配置文件主要由3部分构造，ipvs配置，全局配置，VRRP配置。
代码语言：javascript复制# 全局配置（全局配置有Global definitions和Static routes/address，全局定义和静态路由）
global_defs
{
...
}
# 配置vrrp实例（VRRP实例和VRRP同步组）
# vrrp instance # 虚拟路由器，VRRP实例
vrrp_instance NAME {
...
}
# vrrp synchronization group # VRRP同步组
vrrp_sync_group NAME {
...
}
# ipvs的相关配置
# LVS CONFIGURATION：
# 集群服务，服务内的RS
Virtual server groups
Virtual server #ipvs集群的vs和rs
下面为具体的参数解释
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
# 全局配置（全局配置有Global definitions和Static routes/address，全局定义和静态路由）
global_defs {
# 全局部分定义邮件报警系统，定义邮件发送目标，收件人邮箱地址
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
# 定义发件人邮箱地址
notification_email_from Alexandre.Cassen@firewall.loc
# 定义邮件发送服务器IP，本地发送写localhost
smtp_server 192.168.200.1
# 定义邮件服务器建立连接的超时时长
smtp_connect_timeout 30
# 标识keepalived服务器的字符串，物理节点的标识符；
router_id LVS_DEVEL
# 如果通告与接收的上一个通告来自相同的master路由器，则不执行检查
vrrp_skip_check_adv_addr
# 严格遵守VRRP协议，这一项最好关闭（加感叹号），若不关闭，可用vip无法被ping通
! vrrp_strict
# 在一个接口发送的两个免费ARP之间的延迟，可以精确到毫秒级（默认是0）
vrrp_garp_interval 0
vrrp_gna_interval 0
# IPV4多播地址，默认224.0.0.18
vrrp_mcast_group4 225.0.0.18
}
# 检查调用
vrrp_script <SCRIPT_NAME> { # 脚本名，后面要基于脚本名来进行调用
script "/etc/keepalived/chk_script.sh" # 执行的命令或脚本
interval INT # 每隔多少时间，这个监控脚本要执行一次
weight -INT # 失败了，当前节点的权重要减去多少,对于“weight”值的设置，有一个简单的标准，即“weight”值的绝对值要大于Master和Backup节点“priority”值之差
}
# 虚拟路由器，VRRP实例
vrrp_instance VI_1 {
# 定义实例的角色状态是master还是backup，在当前VRRP实例中此节点的初始状态
state MASTER
# 定义vrrp绑定的接口，即接收或发送心跳通告的接口，即HA监测接口
interface eth0
# 虚拟路由标识(VRID)，同一实例该数值必须相同，即master和backup中该值要相同
virtual_router_id 51
# 该vrrp实例中本机的keepalived的优先级，优先级最高的为master（可用范围0-255）
# 该选项的优先级高于state选项，
# 即若state指定的是backup，但这里设置的值最高，则仍为master
priority 100
# 心跳信息发送和接收时间间隔，单位为秒
advert_int 1
# 认证方式，同一实例中这个配置必须完全一样才可通过认证，只建议使用PASS认证
authentication {
# 使用简单字符认证的方式
auth_type PASS
# 最多支持8字符，超过8字符将只取前8字符
auth_pass 1111
}
# 设置的VIP，当master出现故障后，VIP会故障转移到backup
virtual_ipaddress {
# 一般情况下我们只设置一个VIP地址，也可以设置多个
# 这些vip默认配置在interface指定的接口别名上，可使用dev选项来指定网卡: 192.168.200.19/24 dev eth1
# 使用ip add的方式添加，若要被ifconfig查看，在IP地址后加上label即可
192.168.200.16
192.168.200.17
192.168.200.18
}
# 调用检查
track_script {
chk_service
}
# 使用非抢占模式
nopreempt
#非抢占式：如果backup路由器工作在此模式下，则若Master路由器没有出现故障，backup即使随后被配置了更高的优先级也不会成为Master
# 使用延迟抢占模式
preempt_delay TIME
#抢占式：如果backup路由器工作在抢占方式下，当它收到VRRP报文后，会将主机的优先级与通告报文中的优先级进行比较，如果主机的优先级比当前的Master路由器的优先级高，就会主动抢占成为Master路由器，否则，将保持Backup状态
notify_master <STRING>|<QUOTED-STRING> # 当切换到master模式时，执行此脚本
notify_backup <STRING>|<QUOTED-STRING> # 当切换到backup模式时，执行此脚本
notify_fault <STRING>|<QUOTED-STRING> # 当切换到fault模式时，执行此脚本
notify <STRING>|<QUOTED-STRING>
}
服务检查
在上面的Demo的基础上，我们添加一个检查脚本,使用下面的检查策略。来检查httpd服务是否可用
代码语言：javascript复制┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl status httpd > /dev/null
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$echo $?
0
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl stop httpd.service
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl status httpd > /dev/null
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$echo $?
3
也可以這樣
代码语言：javascript复制┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl is-active httpd -q
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$echo $?
3
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl start httpd
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl is-active httpd -q
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$echo $?
0
或者這樣
代码语言：javascript复制┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl show httpd -p ActiveState
ActiveState=active
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl show httpd -p ActiveState | sed 's/ActiveState=//g'
active
是否运行和是否活跃是两个概念，对于某些一次性服务可以使用下面的方式验证
代码语言：javascript复制┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl show httpd -p ActiveState | cut -d'=' -f2
active
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$systemctl show httpd -p SubState | cut -d'=' -f2
running
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$
keepalived部署服务健康检查剧本
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat keepaliveds.yaml
---
- name: keepalived init
hosts: node
tasks:
- name: install
yum:
name:
- httpd
- keepalived
state: installed
- name: httpd content
shell: "echo `hostname` > /var/www/html/index.html"
- name: Restarted httpd
service:
name: httpd
state: restarted
- name: firewall clons
shell: firewall-cmd --set-default-zone=trusted
# 主机配置
- name: vms153.liruilongs.github.io config
hosts: 192.168.26.153
tags:
- master
vars:
role: MASTER
priority: 100
tasks:
- name: copy keeplived config
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
- name: copy che_service
copy:
content: "#!/bin/shnsystemctl is-active httpd -q"
dest: /etc/keepalived/che_service.sh
backup: yes
mode: '0755'
- name: restart keepalived
service:
name: keepalived
state: restarted
# 备机配置
- name: vms154.liruilongs.github.io config
hosts: 192.168.26.154
tags:
- backup
vars:
role: BACKUP
priority: 90
tasks:
- name: copy keepalived config
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
- name: copy che_service
copy:
content: "#!/bin/shnsystemctl is-active httpd -q"
dest: /etc/keepalived/che_service.sh
mode: '0755'
backup: yes
- name: restart keepalived
service:
name: keepalived
state: restarted
运行测试
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$curl 192.168.26.200
vms153.liruilongs.github.io
┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible 192.168.26.153 -m service -a 'name=httpd state=stopped'
192.168.26.153 | CHANGED => {
"ansible_facts": {
"discovered_interpreter_python": "/usr/bin/python"
},
"changed": true,
"name": "httpd",
"state": "stopped",
.............
┌──[root@vms152.liruilongs.github.io]-[~]
└─$curl 192.168.26.200
vms154.liruilongs.github.io
┌──[root@vms152.liruilongs.github.io]-[~]
└─$
配置文件模板
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$cat keepalived.conf.j2
! Configuration File for keepalived
global_defs {
router_id LVS_DEVEL #设置路由ID,可以和主机名相同，也可以随便定义
vrrp_iptables #手动添加(禁止设置防火墙规则，keepalved每次启动都会自动添加防火墙拒绝所有的规则)
}
vrrp_script chk_service {
script /etc/keepalived/che_service.sh
interval 2
}
vrrp_instance VI_1 {
state {{ role }}
interface ens32 #定义网络接口，根据自己虚拟机上的网卡修改
virtual_router_id 51 #主备服务器VRID号必须保持一致
priority {{ priority }} #服务器优先级，优先级高则优先获得浮动IP
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.26.200
}
track_script {
chk_service
}
}
这个剧本调了好些时间，需要注意的是，配置文件不能有其他的非空格的字符，检查脚本要记得授权，如果没有执行检查脚本，可以看下 /var/log/messages 日志文件
┌──[root@vms153.liruilongs.github.io]-[/etc/keepalived]
└─$cat /var/log/messages | grep -C 10 track
keepalived 角色编写
我们也可以把上面的剧本编写为角色，需要把handlers和和其他的东西抽出来
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible-galaxy init keepalived --init-path=./roles
- Role keepalived was created successfully
┌──[root@vms152.liruilongs.github.io]-[~]
└─$ansible-galaxy list
# /root/roles
- keepalived, (unknown version)
┌──[root@vms152.liruilongs.github.io]-[~]
└─$
编写task
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$cat tasks/main.yml
---
# tasks file for keepalived
# 安装 keepalived
- name: Install keepalived
yum:
name: keepalived
state: latest
tags: keepalived
notify: restart keepalived
# copy 配置文件
- name: Keepalived configuration
template:
src: keepalived.conf.j2
dest: /etc/keepalived/keepalived.conf
notify: restart keepalived
# copy 检查脚本
- when: check_service_name | default(False)
name: Install check script
copy:
content: "#!/bin/shnsystemctl is-active {{ check_service_name }} -q"
dest: /etc/keepalived/che_service.sh
backup: yes
mode: 0755
owner: root
group: root
notify: restart keepalived
# 启动 服务
- name: Start keepalived
service:
name: keepalived
state: started
enabled: yes
编写handlers
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$cat handlers/main.yml
---
# handlers file for keepalived
- name: restart keepalived
service:
name: keepalived
state: restarted
┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$
编写template
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$cat templates/keepalived.conf.j2
! Configuration File for keepalived
global_defs {
router_id LVS_DEVEL #设置路由ID,可以和主机名相同，也可以随便定义
vrrp_iptables #手动添加(禁止设置防火墙规则，keepalved每次启动都会自动添加防火墙拒绝所有的规则)
}
vrrp_script chk_service {
script /etc/keepalived/che_service.sh
interval 2
}
vrrp_instance VI_1 {
state {{ keep_role }}
interface {{ keep_interface }} #定义网络接口，根据自己虚拟机上的网卡修改
virtual_router_id 51 #主备服务器VRID号必须保持一致
{% if keep_role.lower() == 'master' %}
priority {{ keep_priority }}
{% else %}
priority {{ keep_backup_priority }}
{% endif %}
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
{{ virtual_ipaddress }} dev {{ keep_interface }}
}
track_script {
chk_service
}
}
┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$
编写defaults变量
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$cat defaults/main.yaml
---
keep_role: "master"
keep_priority: 100
keep_backup_priority: 50
keep_interface: "ens32"
virtual_ipaddress: "192.168.26.200"
check_service_name: httpd
编写调用剧本
代码语言：javascript复制┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$cat tests/test.yml
---
- hosts: 192.168.26.153
vars:
keep_role: MASTER
roles:
- keepalived
- hosts: 192.168.26.154
vars:
keep_role: BACKUP
roles:
- keepalived
┌──[root@vms152.liruilongs.github.io]-[~/roles/keepalived]
└─$
博文参考
https://www.keepalived.org/manpage.html
https://www.cnblogs.com/hgzero/p/13718516.html
https://unix.stackexchange.com/questions/396630/the-proper-way-to-test-if-a-service-is-running-in-a-script
https://github.com/tcomerma/ansible-keepalived/
https://github.com/demis-svenska/aws-echis/tree/master/src/commcare_cloud/ansible/roles/keepalived
