SaltStack实例:Keepalived+Redis高可用架构
Keepalived+Redis是一种比较成熟的Redis高可用解决方案,通过keepalived实现虚拟ip(vip)的切换以及Reids进程监控,并控制Redis的主从同步状态。以下是架构图:http://s1.运维网.com/images/20180831/1535680722192491.png
环境介绍:
Saltstack-master: 192.168.39.185
Master:192.168.39.100
Slave:192.168.39.101
VIP:192.168.39.23
高可用状态情况:
1)当Master端与Slave端都运行正常时,Master负责服务,Slave作为备用。
2)当Master端运行不正常时,slave接管服务,同时关闭主从复制功能。
3)当Master端恢复正常时,则从slave同步数据,作为Slave的从,不切换成主。
4)当slave端挂掉,master端恢复成主。
以下通过saltstack完成keepalived+redis的高可用架构部署:
首先,修改master配置文件指定top file文件路径:
# vim /etc/salt/master
file_roots:
base:
- /srv/salt修改salt配置文件需要重启服务。
整个状态文件目录结构如下:
http://s1.运维网.com/images/20180831/1535685120759290.png
设置主从模式的Grains(Grains为模版文件设置变量,通常也可以用Pillar设置):
设置master端和slave端的Grains,指定role、vip和redis的master_ip:
# salt "centos7-1" grains.setvals "{'role':'master','vip':'192.168.39.23','master_ip':'192.168.39.101'}"
# salt "centos7-2" grains.setvals "{'role':'slave','vip':'192.168.39.23','master_ip':'192.168.39.100'}"可以查看到Grains已经设置成功:
http://s1.运维网.com/images/20180831/1535682628537336.png
设置入口文件top.sls:
以list匹配方式对两台主机应用对应模块:
# cat top.sls
base:
'centos7-1,centos7-2':
- match: list
- redis
- keepalived一、部署Redis
安装redis并根据角色下发配置模版文件。
Redis安装入口文件:
# cat init.sls
include:
- .install_redis
- .redis_running
- .redis_confRedis安装:
# cat install_redis.sls
{% for s in ["jemalloc-3.6.0-1.el7.x86_64.rpm","redis-3.2.12-1.el7.x86_64.rpm",] %}
copy_{{ s }}:
file.managed:
- name: /usr/local/src/{{ s }}
- source: salt://redis/file/{{ s }}
- user: root
- group: root
- template: jinja
- mode: 755
{% endfor %}
install_redis:
cmd.run:
- name: cd /usr/local/src/ && yum install -y redis-3.2.12-1.el7.x86_64.rpm jemalloc-3.6.0-1.el7.x86_64.rpm
- require:
- file: copy_redis-3.2.12-1.el7.x86_64.rpm这里通过require指定依赖关系,将rpm都下发到节点下之后,进行安装redis。
Redis配置洗发以及创建目录:
# cat redis_conf.sls
redis_conf:
file.managed:
- name: /etc/redis.conf
- source: salt://redis/templates/redis.j2
- user: root
- group: root
- template: jinja
- mode: 644
- require:
- cmd: install_redis
redis_dir:
cmd.run:
- name: mkdir -pv /data/redis && chown redis.redis /data/redis
- unless: test -d /data/redis unless指定通过test命令判断目录是否存在,如果不存在则执行name。
Redis服务启动控制:
# cat redis_running.sls
redis_running:
service.running:
- name: redis
- enable: True
- require:
- cmd: install_redis
- watch:
- file: redis_conf通过watch状态监控,如果就重启服务。
Redis配置文件模版:
# grep -v "#" redis.j2
bind 0.0.0.0
protected-mode yes
port 6379
tcp-backlog 511
timeout 0
tcp-keepalive 300
daemonize no
supervised no
pidfile /var/run/redis/redis.pid
loglevel notice
logfile /var/log/redis/redis.log
databases 16
save 900 1
save 300 10
save 60 10000
stop-writes-on-bgsave-error yes
rdbcompression yes
rdbchecksum yes
dbfilename dump.rdb
dir /data/redis/
{% if grains['role'] == "slave" %}
slaveof {{grains['master_ip']}} 6379
{% endif %}
slave-serve-stale-data yes
slave-read-only yes
repl-diskless-sync no
repl-diskless-sync-delay 5
repl-disable-tcp-nodelay no
slave-priority 100
appendonly no
appendfilename "appendonly.aof"
appendfsync everysec
no-appendfsync-on-rewrite no
auto-aof-rewrite-percentage 100
auto-aof-rewrite-min-size 64mb
aof-load-truncated yes
lua-time-limit 5000
slowlog-log-slower-than 10000
slowlog-max-len 128
latency-monitor-threshold 0
notify-keyspace-events ""
hash-max-ziplist-entries 512
hash-max-ziplist-value 64
list-max-ziplist-size -2
list-compress-depth 0
set-max-intset-entries 512
zset-max-ziplist-entries 128
zset-max-ziplist-value 64
hll-sparse-max-bytes 3000
activerehashing yes
client-output-buffer-limit normal 0 0 0
client-output-buffer-limit slave 256mb 64mb 60
client-output-buffer-limit pubsub 32mb 8mb 60
hz 10
aof-rewrite-incremental-fsync yes 二、部署keepalived
keepalived入口文件:
# cat init.sls
include:
- .install_keepalived
- .keepalived_running
- .keepalived_conf keepalived安装文件:
# cat install_keepalived.sls
install_keepalived:
pkg.installed:
- name: keepalivedpkg指定通过yum源进行安装。
keepalived配置下发以及创建目录:
# cat keepalived_conf.sls
keepalived_conf:
file.managed:
- name: /etc/keepalived/keepalived.conf
- source: salt://keepalived/templates/keepalived.conf
- user: root
- group: root
- template: jinja
- mode: 644
- require:
- pkg: install_keepalived
- cmd: scripts_dir
scripts_dir:
cmd.run:
- name: mkdir -pv /etc/keepalived/scripts/
- unless: test -d /etc/keepalived/scripts/
{% for s in ["redis_backup.sh","redis_check.sh","redis_fault.sh","redis_master.sh","redis_stop.sh"] %}
keepalived_{{s}}:
file.managed:
- name: /etc/keepalived/scripts/{{s}}
- source: salt://keepalived/templates/scripts/{{s}}
- user: root
- group: root
- template: jinja
- mode: 755
- require:
- pkg: install_keepalived
{% endfor %}keepalived服务启动文件:
# cat keepalived_running.sls
keepalived_running:
service.running:
- name: keepalived
- enable: True
- require:
- pkg: install_keepalived
- watch:
- file: keepalived_confkeepalived模板文件和脚本文件:
keepalived.conf主配置文件根据role值动态下发配置文件:
# cat keepalived.conf
! Configuration File for keepalived
vrrp_script chk_redis {
script "/etc/keepalived/scripts/redis_check.sh"
interval 2
}
vrrp_instance VI_1 {
{% if grains['role'] == 'master' %}
state MASTER
{% else %}
state BACKUP
{% endif %}
interface eth0
virtual_router_id 51
{% if grains['role'] == "master" %}
priority 101
{% else %}
priority 100
{% endif %}
# advert_int 1
nopreempt
authentication {
auth_type PASS
auth_pass redis
}
track_script {
chk_redis
}
virtual_ipaddress {
{{ grains['vip'] }}
}
notify_master /etc/keepalived/scripts/redis_master.sh
notify_backup /etc/keepalived/scripts/redis_backup.sh
notify_fault /etc/keepalived/scripts/redis_fault.sh
notify_stop /etc/keepalived/scripts/redis_stop.sh
} keepalived配置的几个脚本,当keeplaived在转换状态时会按照状态来呼叫:
当进入master状态时会呼叫notify_master;
当进入backup状态时会呼叫notify_backup;
当发现异常情况时进入fault状态呼叫notify_fault;
当keepalived程序终止时则呼叫notify_stop。
redis_backup.sh-Redis健康检测脚本:
# cat redis_check.sh
#!/bin/bash
#
ALIVE=`/usr/bin/redis-cli PING`
if [ "$ALIVE" == "PONG" ];then
echo $ALIVE
exit 0
else
echo $ALIVE
exit 1
firedis_master.sh-切换master触发执行脚本:
# cat redis_master.sh
#!/bin/bash
#
REDISCLI="/usr/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "" >> $LOGFILE
date >> $LOGFILE
echo "Being master..." >> $LOGFILE 2>&1
echo "run slaveof no one cmd..." >> $LOGFILE
$RESISCLI SLAVEOF {{ grains['master_ip']}} 6479>> $LOGFILE 2>&1
$REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1redis_backup.sh-切换成backup角色执行脚本:
# cat redis_backup.sh
#!/bin/bash
#
REDISCLI="/usr/bin/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "" >> $LOGFILE
date >> $LOGFILE
echo "being salve..." >> $LOGFILE 2>&1
#sleep 25
echo "run slaveof cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF {{ grains['master_ip'] }} 6379 $LOGFILE 2>&1redis_fault.sh-进入fault状态执行脚本:
# cat redis_fault.sh
#!/bin/bash
#
$LOGFILE=/var/log/keepalived-redis-state.log
echo "" >> $LOGFILE
date >> $LOGFILEredis_stop.sh-当keepalived服务终止时执行此脚本:
# cat redis_stop.sh
#!/bin/bash
#
LOGFILE=/var/log/keepalived-redis-state.log
echo "" >> $LOGFILE
date >> $LOGFILE所有状态配置文件和脚本设置完成执行:
在执行时我们可以通过指定参数,模拟执行:
# salt 'centos7-' state.highstate test=True 测试执行没有其他问题,执行安装:
# salt 'centos7-' state.highstate执行结构如下:
http://s1.运维网.com/images/20180831/1535684778183530.png
会看到centos7-1节点,执行完成之后的状态:
http://s1.运维网.com/images/20180831/1535684863490145.png
测试keepalived+redis高可用:
登陆centos7-1查看vip情况:http://s1.运维网.com/images/20180831/1535685439507624.png
在saltstack服务端通过连接vip测试登陆情况:
http://s1.运维网.com/images/20180831/1535686309230533.png
关闭centos7-1下的redis服务:
# service redis stop
Redirecting to /bin/systemctl stopredis.service
# service redis status
Redirecting to /bin/systemctl statusredis.service
● redis.service - Redis persistent key-value database
Loaded: loaded (/usr/lib/systemd/system/redis.service; enabled; vendor preset: disabled)
Drop-In: /etc/systemd/system/redis.service.d
└─limit.conf
Active: inactive (dead) since Fri 2018-08-31 11:41:44 CST; 5s ago
Process: 6414 ExecStop=/usr/libexec/redis-shutdown (code=exited, status=0/SUCCESS)
Process: 6147 ExecStart=/usr/bin/redis-server /etc/redis.conf --supervised systemd (code=exited, status=0/SUCCESS)
Main PID: 6147 (code=exited, status=0/SUCCESS)
Aug 31 11:40:17 centos7-1 systemd: Starting Redis persistent key-value database...
Aug 31 11:40:17 centos7-1 systemd: Started Redis persistent key-value database.
Aug 31 11:41:44 centos7-1 systemd: Stopping Redis persistent key-value database...
Aug 31 11:41:44 centos7-1 systemd: Stopped Redis persistent key-value database.重新连接vip登陆redis查看设置name值:
http://s1.运维网.com/images/20180831/1535687103428210.png
登陆centos7-2下查看vip切换情况:http://s1.运维网.com/images/20180831/1535687156561448.png
参考文献:《saltstack运维实战》
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