• 基于ssh,shell,python,iptables,fabric,supervisor和模板文件的多服务器配置管理


     前言:略

    新服务器:NS   主服务器:OS

    一:OS上新建模板目录例如 mkdir bright 用于导入一些不方便在远程修改的配置文件、redis.conf等,到需要配置的步骤时用远程cp命令覆盖掉

    (重要:覆盖后要记得执行chmod修改文件必要的权限,传过去的文件权限会变 例如 chmod 755 /etc/rc.local)

    除了配置文件外还有:xxx.sh shell文件将多命令放到一起

    例如

    1 export LC_ALL=C
    2 pip install update
    3 apt-get install python-pip
    4 pip install -i http://pypi.douban.com/simple/ saltTesting
    5 pip install -r requirements.txt
    6 pip install pexpect
    7 pip install pymongo==3.2
    8 pip install tornado
    9 pip install supervisor
    start.sh

    其中有一句

    pip install -r requirements.txt

    这是在OS上  pip freeze > requirements.txt 得到的环境依赖(当然执行的时候有些会因为版本之类的问题跑失败,那么测试时要找出无法执行的在requirements.txt中去掉并找到合适的安装命令写到shell 例如start.sh中)

    简单的安装如此做即可,像redis,nginx等复杂安装我们用python脚本来做(一是为了更好的控制命令,可以利用灵活的语法变更一些配置,自由定制。二是方便保存下来重复利用,除了这个项目拿到别的地方也可以继续用。)

    例如一键(git提交代码,安装redis,安装mongo,安装nginx)脚本,这个只是示例,具体自己适配吧,写的比较简单

      1 #coding:utf-8
      2 import subprocess
      3 import datetime
      4 import time
      5 import random
      6 import sys
      7 import os
      8 
      9 MONGO = 'https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.0.6.tgz'
     10 REDIS = 'http://download.redis.io/releases/redis-3.0.7.tar.gz'
     11 NGINX ='http://nginx.org/download/nginx-1.9.15.tar.gz'
     12 MONGOTAR ='mongodb-linux-x86_64-3.0.6.tgz'
     13 MONGODIR ='mongodb-linux-x86_64-3.0.6'
     14 REDISTAR ='redis-3.0.7.tar.gz'
     15 REDISDIR ='redis-3.0.7'
     16 NGINXTAR ='nginx-1.9.15.tar.gz'
     17 NGINXDIR = 'nginx-1.9.15'
     18 
     19 SUDOPWD = 'bright'
     20 
     21 print datetime.datetime.now()
     22 
     23 print "当前支持功能 :  0:自定义命令文本 1:git一键提交代码 2:一键mongo安装
    3:一键redis安装(执行一遍后需要手动更改( vi /usr/local/redis/etc/redis.conf )中daemon = yes bind 127.0.0.1再次执行) 
    4:一键nginx安装(执行一遍后需要手动更改(vi /usr/local/nginx/etc/nginx.conf)再次执行) 
    使用技巧:当前0是直接复制history命令粘贴形式,如其他形式更方便使用可自行更改strcmds函数。 "
     24 FUNCTIONS = input("输入功能 :" )
     25 
     26 def strcmds(file):
     27     f = open(file)
     28     lines = f.readlines()
     29     data=[]
     30     for line in lines:
     31     temp = line.replace("
    ", "")
     32         temp=temp[7:]
     33         data.append(temp)
     34     print data
     35     return data
     36 
     37 def shcall(cmd):
     38     if cmd[0] == 's' and cmd[1] == 'u' and cmd[2] == 'd':
     39         #f = open("adpwd.txt","w")
     40         #f.write(SUDOPWD)
     41         p=subprocess.Popen(cmd,shell=True,close_fds=True,universal_newlines=True,stdin=subprocess.PIPE,stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
     42         p.stdin.write(b'%s
    ' % SUDOPWD)
     43         #f.close()
     44     else:
     45         p=subprocess.Popen(cmd,shell=True,close_fds=True,universal_newlines=True,stdin=subprocess.PIPE,stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
     46     while p.poll() == None:
     47         time.sleep(0.1)
     48         print p.stdout.readline()
     49     print p.stdout.read()
     50     #print 'returen code:', p.returncode
     51 
     52 def showmsg(count,cmds):
     53     print "luckynum: ",random.randint(0,999),"Connect me WeChat: brightlike"
     54     print 'Your work has done: ',"%.2f" % round(float(count)*100/len(cmds),2),'%'
     55 
     56 def main():
     57     count = 0
     58     if FUNCTIONS == 0:
     59         cmds=strcmds('a.txt') #redis
     60         for i in cmds:
     61             print i
     62             if i[0] == 'v' and i[1] == 'i':
     63                 print 'vim process'
     64             shcall(i)
     65             if i[0] == 's' and i[1] == 'u' and i[2] == 'd':
     66                 print 'admin process'
     67             shcall(i)
     68         count = count+1
     69             showmsg(count,cmds)
     70     if FUNCTIONS == 1:
     71         cmds=['git status','git add -A .','git commit -a -m "fast commit all"','git push','git status']
     72         for i in cmds:
     73             with open('git.txt','wr') as f:
     74                 f.write('%s
    ' % i)
     75             print i
     76             if i[4] == 'p' and i[5] == 'u' and i[6] == 's':
     77                 print 'push process'
     78             shcall(i)
     79             else:
     80                 shcall(i)
     81         count = count+1
     82             showmsg(count,cmds)
     83     if FUNCTIONS == 2:  #pip install pymongo==3.2
     84         cmds=['sudo chmod 777 /usr/local','sudo mkdir -p /data/db','mkdir /usr/local/mongodb','curl -O %s' % MONGO,'tar -zxvf %s' % MONGOTAR,'mv %s/ /usr/local/mongodb' % MONGODIR,'export PATH=<mongodb-install-directory>/bin:$PATH','export LC_ALL=C','echo "/usr/local/mongodb/bin/mongod --dbpath=/usr/local/mongodb/data –logpath=/usr/local/mongodb/logs –logappend  --auth –port=27017" >> /etc/rc.local','mongod --repair','./mongod --dbpath=/data/db --rest','sudo find /usr/local -name mongodb.conf']
     85         for i in cmds:
     86             with open('mongo.txt','wr') as f:
     87                 f.write('%s
    ' % i)
     88             print i
     89             shcall(i)
     90         count = count+1
     91             showmsg(count,cmds)
     92     if FUNCTIONS == 3:  #pip install redis
     93         if os.path.exists('/usr/local/redis/etc/'):
     94             cmds=['find /usr/local -name redis.conf','/usr/local/redis/bin/redis-server /usr/local/redis/etc/redis.conf','ps aux |grep redis']
     95         cmds=['find /usr/local -name redis.conf','/usr/local/redis/bin/redis-server /usr/local/redis/etc/redis.conf','ps aux |grep redis','sudo chmod 777 /usr/local','mkdir -p /usr/local/redis/bin','mkdir -p /usr/local/redis/etc','curl -O %s' % REDIS,'tar xvf %s' % REDISTAR,'mv %s /usr/local' % REDISDIR,'export DESTDIR=/usr/local/%s' % REDISDIR,'./configure --prefix=/usr/local/%s' % REDISDIR,'make -C /usr/local/%s && make install -C /usr/local/%s' % (REDISDIR,REDISDIR),'cp /usr/local/%s/redis.conf /usr/local/redis/etc' % REDISDIR,'cp -r /usr/local/%s/src/. /usr/local/redis/bin' % REDISDIR]
     96         for i in cmds:
     97             with open('redis.txt','wr') as f:
     98                 f.write('%s
    ' % i)
     99             print i
    100             shcall(i)
    101         count = count+1
    102             showmsg(count,cmds)
    103     if FUNCTIONS == 4:  #pip install nginx
    104         if os.path.exists('/usr/local/%s/' % NGINXDIR):
    105             cmds=['find /usr/local -name nginx.conf','/usr/local/nginx/etc/nginx.conf start','ps aux |grep nginx']
    106         cmds=['yum -y install pcre-devel','yum -y install openssl openssl-devel','pip install pcre-devel','pip install install openssl openssl-devel','curl -O %s' % NGINX,'tar xvf %s' % NGINXTAR,'mkdir -p /usr/local/nginx/bin','mkdir -p /usr/local/nginx/etc','mv %s /usr/local' % NGINXDIR,'export DESTDIR=/usr/local/%s' % NGINXDIR,'cd /usr/local/%s && ./configure' % NGINXDIR,'make -C /usr/local/%s && make install -C /usr/local/%s' % (NGINXDIR,NGINXDIR),'cp /usr/local/%s/nginx.conf /usr/local/nginx/etc' % NGINXDIR,'find /usr/local -name nginx.conf']
    107         for i in cmds:
    108             print i
    109             shcall(i)
    110         count = count+1
    111             showmsg(count,cmds)
    112     print "Hope you happy to work, even working on computer every day is boring.
    Connect me WeChat: brightlike"
    113     #shcall('ping -c 10 -i 0.5 119.75.217.109')
    114 
    115 if __name__ == '__main__':
    116     main()
    shells.py

    二.ssh 有了稳定连接的可能才可以谈远程配置

    OS:

    cat .ssh/id_rsa.pub  查看key

    NS:  

    ssh-keygen -t rsa -C “”  (引号内输入便于识别内容) 生成ssh目录及公钥 

    vi .ssh/authorized_keys  添加OS上key

    三:fabric 本文核心 远程操作基于此工具  安装: pip install fabric

    命令执行规则  : fabric + fabfile.py文件中函数名 例 fab setup

    示例代码

     1 #coding:utf-8
     2 from fabric.api import *
     3 import os
     4 #传文件后记得更改文件权限
     5 SENDROUTE ='/root'
     6 SENDFILE ='start.sh' 
     7 env.hosts=['111.111.111.111:1111','222.222.222.222']#服务器列表
     8 #进行角色分组,需要安装的服务器,后期优化的服务器等等
     9 env.roledefs = {
    10        'setup':['111.111.111.111:1111','222.222.222.222'],        
    11    'seo'['111.111.111.111:1111','222.222.222.222:2222','3.3.3.3']
    12 }
    13 #下面这行语法是指定哪些角色服务器执行,这里是安装,不用这行代表对env.hosts列表中服务器执行
    14 @roles ('setup')
    15 def setup():
    16     with lcd('/root'):#lcd是在本地目录运行命令
    17         with settings(warn_only=True):
    18             result = put("/root/xxx.tar")   #xxx.tar为本机上打包的所有的模板文件和程序代码功能模块等
    19         if result.failed and not confirm("put file failed, Continue[Y/N]?"):
    20             abort("Aborting file put task!")
    21     with cd('/root'):#cd为在远程服务器上运行命令
    22         run('tar zxvf xxx.tar && rm -f xxx.tar')
    23     with cd('/root/bright'):
    24         run('bash start.sh')
    25 #这后面都是对应执行命令只举这一个例子,这里是mongo安装
    26     with cd('/root/bright/mongo'):
    27         run('python mongo.py')
    28         run('bash mongo.sh')
    29 
    30 
    31 #单独传文件主要安装配置后优化更新代码用
    32 def send():
    33     with cd('%s' % SENDROUTE):
    34         with settings(warn_only=True):
    35             result = put("%s/%s" % (SENDROUTE,SENDFILE))
    36             with cd('/root'):
    37                 run('mv %s %s' % (SENDFILE,SENDROUTE))
    38                 run('chmod 755 %s/%s' % (SENDROUTE,SENDFILE))
    39         if result.failed and not confirm("put file failed, Continue[Y/N]?"):
    40             abort("Aborting file put task!")
    fabfile.py

    需要提前归档好需要的文件和模板目录 tar --exclude=.git --exclude=.ssh -czvf xxx.tar /root (可以排除一些不必要的文件如git等)

    另外还可以写一些查看日志(tail -20 xxx.stderr.log) 的命令,有个技巧,Fabric 与 nohup 的问题

    nohup命令默认是无法直接fabric的,执行不生效,可以曲线救国加延迟(

    run('echo "nohup python main.py  &" > xxx.sh')

    run('bash xxx.sh && sleep 1')

    )解决

    四:shell 解决命令太多等问题,以及安装配置启动文件等

     这里有个获取本地ip的技巧,利用sed拿到,当然这个不一定适用,有些网络环境比较复杂的机器需要稍微更改下匹配语句

    1 ifconfig | sed -En 's/127.0.0.*//;s/.*inet (addr:)?(([0-9]*.){3}[0-9]*).*/2/p'
    get_ip.sh
    ifconfig | sed -En 's/127.0.0.*//;s/192.168.*//;s/172.*//;s/10.[0-255].*.*//;s/.*inet (addr:)?(([0-9]*.){3}[*0-9]*).*/2/p'  #这里去掉了局域网

    拿到ip后我们要用到需要更改ip的模板文件上,再来个bash

    1 cmd="s/{HOST_IP}/"$(bash get_ip.sh)"/"
    2 sed -i "$cmd" /root/bright/xxx.py  #xxx.py为模板文件 需要更改为当前ip的地方提前改成HOST = '{HOST_IP}'
    replace_ip.sh

    五:supervisor 进程管理工具,安装 :pip install supervisor

    配置文件直接放到模板目录里

     1 [unix_http_server]
     2 file = /var/run/supervisor.sock
     3 chmod = 0777
     4 chown= root:root
     5 
     6 [inet_http_server]
     7 # Web管理界面设定
     8 port=11111#(端口自定)
     9 username = bright
    10 password = bright
    11 
    12 [rpcinterface:supervisor]
    13 supervisor.rpcinterface_factory = supervisor.rpcinterface:make_main_rpcinterface
    14 
    15 [supervisorctl]
    16 serverurl = unix:///var/run/supervisor.sock
    17 
    18 [supervisord]
    19 logfile=/var/log/supervisord/supervisord.log    ;(main log file;default $CWD/supervisord.log)
    20 logfile_maxbytes=50MB       ;(max main logfile bytes b4 rotation;default 50MB)
    21 logfile_backups=10          ; (num of main logfile rotation backups;default 10)
    22 loglevel=info               ; (log level;default info; others: debug,warn,trace)
    23 pidfile=/var/run/supervisord.pid        ;(supervisord pidfile;default supervisord.pid)
    24 #nodaemon=true              ; (start in foreground if true;default false)
    25 minfds=1024                ; (min. avail startup file descriptors;default 1024)
    26 minprocs=200                ; (min. avail process descriptors;default 200)
    27 user=root                ; (default is current user, required if root)
    28 #下面为示例项目启动,有些项目会有多个进程要跑,按下面格式复用即可
    29 [program:xxx]
    30 directory=/root/xxx/xxx
    31 command =python main.py
    32 user = root
    33 autostart = true
    34 autoresart = true
    35 stderr_logfile = /var/log/supervisor/xxx.stderr.log
    36 stdout_logfile = /var/log/supervisor/xxx.stdout.log
    supervisord.conf

    当然现在还无法开机或reboot自启,还需要再来个bash脚本

    1 cp /root/bright/supervisord.conf /etc/
    2 mkdir /var/log/supervisor     #没有log文件路径可能会报错
    3 cp /root/bright/rc.local /etc/
    4 chmod 755 /etc/rc.local      #rc.local为自启文件
    5 chmod 755 /etc/supervisord.conf
    autorun.sh
     1 #!/bin/sh -e
     2 #
     3 # rc.local
     4 #
     5 # This script is executed at the end of each multiuser runlevel.
     6 # Make sure that the script will "exit 0" on success or any other
     7 # value on error.
     8 #
     9 # In order to enable or disable this script just change the execution
    10 # bits.
    11 #
    12 # By default this script does nothing.
    13 supervisord -c /etc/supervisord.conf
    14 exit 0  #如有其它也需要自启却不用supervisor的可以加在此句之前,保存后记得ls -l /etc/rc.local检查下文件权限,如还不能自启可尝试运行dpkg-reconfigure dash 选择NO选项
    rc.local

    六: iptables 配置过滤规则,尽可能避免外部入侵,如数据库等

    这里举个防止redis入侵的情况,不小心把端口开在可公网是十分危险的,默认启动redis是暴露在公网,所以配置文件中bind ip那里切记修改为本地127.0.0.1,运行时也要通过配置文件跑

    1 iptables -F
    2 iptables -A INPUT -p tcp -s 127.0.0.1 --dport 6379 -j ACCEPT #6379为redis默认启动端口,其它照葫芦画瓢即可,iptables要配置谨慎,不然自己都连不上去会很惨,嗯嗯
    3 iptables -A INPUT -p tcp --dport 6379 -j DROP
    iptables.sh

    示例redis.conf(文件较长)

      1 # Redis configuration file example.
      2 #
      3 # Note that in order to read the configuration file, Redis must be
      4 # started with the file path as first argument:
      5 #
      6 # ./redis-server /path/to/redis.conf
      7 
      8 # Note on units: when memory size is needed, it is possible to specify
      9 # it in the usual form of 1k 5GB 4M and so forth:
     10 #
     11 # 1k => 1000 bytes
     12 # 1kb => 1024 bytes
     13 # 1m => 1000000 bytes
     14 # 1mb => 1024*1024 bytes
     15 # 1g => 1000000000 bytes
     16 # 1gb => 1024*1024*1024 bytes
     17 #
     18 # units are case insensitive so 1GB 1Gb 1gB are all the same.
     19 
     20 ################################## INCLUDES ###################################
     21 
     22 # Include one or more other config files here.  This is useful if you
     23 # have a standard template that goes to all Redis servers but also need
     24 # to customize a few per-server settings.  Include files can include
     25 # other files, so use this wisely.
     26 #
     27 # Notice option "include" won't be rewritten by command "CONFIG REWRITE"
     28 # from admin or Redis Sentinel. Since Redis always uses the last processed
     29 # line as value of a configuration directive, you'd better put includes
     30 # at the beginning of this file to avoid overwriting config change at runtime.
     31 #
     32 # If instead you are interested in using includes to override configuration
     33 # options, it is better to use include as the last line.
     34 #
     35 # include /path/to/local.conf
     36 # include /path/to/other.conf
     37 
     38 ################################ GENERAL  #####################################
     39 
     40 # By default Redis does not run as a daemon. Use 'yes' if you need it.
     41 # Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
     42 daemonize yes
     43 
     44 # When running daemonized, Redis writes a pid file in /var/run/redis.pid by
     45 # default. You can specify a custom pid file location here.
     46 pidfile /var/run/redis/redis-server.pid
     47 
     48 # Accept connections on the specified port, default is 6379.
     49 # If port 0 is specified Redis will not listen on a TCP socket.
     50 port 6379
     51 
     52 # TCP listen() backlog.
     53 #
     54 # In high requests-per-second environments you need an high backlog in order
     55 # to avoid slow clients connections issues. Note that the Linux kernel
     56 # will silently truncate it to the value of /proc/sys/net/core/somaxconn so
     57 # make sure to raise both the value of somaxconn and tcp_max_syn_backlog
     58 # in order to get the desired effect.
     59 tcp-backlog 511
     60 
     61 # By default Redis listens for connections from all the network interfaces
     62 # available on the server. It is possible to listen to just one or multiple
     63 # interfaces using the "bind" configuration directive, followed by one or
     64 # more IP addresses.
     65 #
     66 # Examples:
     67 #
     68 # bind 192.168.1.100 10.0.0.1
     69 bind 127.0.0.1
     70 
     71 # Specify the path for the Unix socket that will be used to listen for
     72 # incoming connections. There is no default, so Redis will not listen
     73 # on a unix socket when not specified.
     74 #
     75 # unixsocket /var/run/redis/redis.sock
     76 # unixsocketperm 700
     77 
     78 # Close the connection after a client is idle for N seconds (0 to disable)
     79 timeout 0
     80 
     81 # TCP keepalive.
     82 #
     83 # If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
     84 # of communication. This is useful for two reasons:
     85 #
     86 # 1) Detect dead peers.
     87 # 2) Take the connection alive from the point of view of network
     88 #    equipment in the middle.
     89 #
     90 # On Linux, the specified value (in seconds) is the period used to send ACKs.
     91 # Note that to close the connection the double of the time is needed.
     92 # On other kernels the period depends on the kernel configuration.
     93 #
     94 # A reasonable value for this option is 60 seconds.
     95 tcp-keepalive 0
     96 
     97 # Specify the server verbosity level.
     98 # This can be one of:
     99 # debug (a lot of information, useful for development/testing)
    100 # verbose (many rarely useful info, but not a mess like the debug level)
    101 # notice (moderately verbose, what you want in production probably)
    102 # warning (only very important / critical messages are logged)
    103 loglevel notice
    104 
    105 # Specify the log file name. Also the empty string can be used to force
    106 # Redis to log on the standard output. Note that if you use standard
    107 # output for logging but daemonize, logs will be sent to /dev/null
    108 logfile /var/log/redis/redis-server.log
    109 
    110 # To enable logging to the system logger, just set 'syslog-enabled' to yes,
    111 # and optionally update the other syslog parameters to suit your needs.
    112 # syslog-enabled no
    113 
    114 # Specify the syslog identity.
    115 # syslog-ident redis
    116 
    117 # Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
    118 # syslog-facility local0
    119 
    120 # Set the number of databases. The default database is DB 0, you can select
    121 # a different one on a per-connection basis using SELECT <dbid> where
    122 # dbid is a number between 0 and 'databases'-1
    123 databases 16
    124 
    125 ################################ SNAPSHOTTING  ################################
    126 #
    127 # Save the DB on disk:
    128 #
    129 #   save <seconds> <changes>
    130 #
    131 #   Will save the DB if both the given number of seconds and the given
    132 #   number of write operations against the DB occurred.
    133 #
    134 #   In the example below the behaviour will be to save:
    135 #   after 900 sec (15 min) if at least 1 key changed
    136 #   after 300 sec (5 min) if at least 10 keys changed
    137 #   after 60 sec if at least 10000 keys changed
    138 #
    139 #   Note: you can disable saving completely by commenting out all "save" lines.
    140 #
    141 #   It is also possible to remove all the previously configured save
    142 #   points by adding a save directive with a single empty string argument
    143 #   like in the following example:
    144 #
    145 #   save ""
    146 
    147 save 900 1
    148 save 300 10
    149 save 60 10000
    150 
    151 # By default Redis will stop accepting writes if RDB snapshots are enabled
    152 # (at least one save point) and the latest background save failed.
    153 # This will make the user aware (in a hard way) that data is not persisting
    154 # on disk properly, otherwise chances are that no one will notice and some
    155 # disaster will happen.
    156 #
    157 # If the background saving process will start working again Redis will
    158 # automatically allow writes again.
    159 #
    160 # However if you have setup your proper monitoring of the Redis server
    161 # and persistence, you may want to disable this feature so that Redis will
    162 # continue to work as usual even if there are problems with disk,
    163 # permissions, and so forth.
    164 stop-writes-on-bgsave-error yes
    165 
    166 # Compress string objects using LZF when dump .rdb databases?
    167 # For default that's set to 'yes' as it's almost always a win.
    168 # If you want to save some CPU in the saving child set it to 'no' but
    169 # the dataset will likely be bigger if you have compressible values or keys.
    170 rdbcompression yes
    171 
    172 # Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
    173 # This makes the format more resistant to corruption but there is a performance
    174 # hit to pay (around 10%) when saving and loading RDB files, so you can disable it
    175 # for maximum performances.
    176 #
    177 # RDB files created with checksum disabled have a checksum of zero that will
    178 # tell the loading code to skip the check.
    179 rdbchecksum yes
    180 
    181 # The filename where to dump the DB
    182 dbfilename dump.rdb
    183 
    184 # The working directory.
    185 #
    186 # The DB will be written inside this directory, with the filename specified
    187 # above using the 'dbfilename' configuration directive.
    188 #
    189 # The Append Only File will also be created inside this directory.
    190 #
    191 # Note that you must specify a directory here, not a file name.
    192 dir /var/lib/redis
    193 
    194 ################################# REPLICATION #################################
    195 
    196 # Master-Slave replication. Use slaveof to make a Redis instance a copy of
    197 # another Redis server. A few things to understand ASAP about Redis replication.
    198 #
    199 # 1) Redis replication is asynchronous, but you can configure a master to
    200 #    stop accepting writes if it appears to be not connected with at least
    201 #    a given number of slaves.
    202 # 2) Redis slaves are able to perform a partial resynchronization with the
    203 #    master if the replication link is lost for a relatively small amount of
    204 #    time. You may want to configure the replication backlog size (see the next
    205 #    sections of this file) with a sensible value depending on your needs.
    206 # 3) Replication is automatic and does not need user intervention. After a
    207 #    network partition slaves automatically try to reconnect to masters
    208 #    and resynchronize with them.
    209 #
    210 # slaveof <masterip> <masterport>
    211 
    212 # If the master is password protected (using the "requirepass" configuration
    213 # directive below) it is possible to tell the slave to authenticate before
    214 # starting the replication synchronization process, otherwise the master will
    215 # refuse the slave request.
    216 #
    217 # masterauth <master-password>
    218 
    219 # When a slave loses its connection with the master, or when the replication
    220 # is still in progress, the slave can act in two different ways:
    221 #
    222 # 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
    223 #    still reply to client requests, possibly with out of date data, or the
    224 #    data set may just be empty if this is the first synchronization.
    225 #
    226 # 2) if slave-serve-stale-data is set to 'no' the slave will reply with
    227 #    an error "SYNC with master in progress" to all the kind of commands
    228 #    but to INFO and SLAVEOF.
    229 #
    230 slave-serve-stale-data yes
    231 
    232 # You can configure a slave instance to accept writes or not. Writing against
    233 # a slave instance may be useful to store some ephemeral data (because data
    234 # written on a slave will be easily deleted after resync with the master) but
    235 # may also cause problems if clients are writing to it because of a
    236 # misconfiguration.
    237 #
    238 # Since Redis 2.6 by default slaves are read-only.
    239 #
    240 # Note: read only slaves are not designed to be exposed to untrusted clients
    241 # on the internet. It's just a protection layer against misuse of the instance.
    242 # Still a read only slave exports by default all the administrative commands
    243 # such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
    244 # security of read only slaves using 'rename-command' to shadow all the
    245 # administrative / dangerous commands.
    246 slave-read-only yes
    247 
    248 # Replication SYNC strategy: disk or socket.
    249 #
    250 # -------------------------------------------------------
    251 # WARNING: DISKLESS REPLICATION IS EXPERIMENTAL CURRENTLY
    252 # -------------------------------------------------------
    253 #
    254 # New slaves and reconnecting slaves that are not able to continue the replication
    255 # process just receiving differences, need to do what is called a "full
    256 # synchronization". An RDB file is transmitted from the master to the slaves.
    257 # The transmission can happen in two different ways:
    258 #
    259 # 1) Disk-backed: The Redis master creates a new process that writes the RDB
    260 #                 file on disk. Later the file is transferred by the parent
    261 #                 process to the slaves incrementally.
    262 # 2) Diskless: The Redis master creates a new process that directly writes the
    263 #              RDB file to slave sockets, without touching the disk at all.
    264 #
    265 # With disk-backed replication, while the RDB file is generated, more slaves
    266 # can be queued and served with the RDB file as soon as the current child producing
    267 # the RDB file finishes its work. With diskless replication instead once
    268 # the transfer starts, new slaves arriving will be queued and a new transfer
    269 # will start when the current one terminates.
    270 #
    271 # When diskless replication is used, the master waits a configurable amount of
    272 # time (in seconds) before starting the transfer in the hope that multiple slaves
    273 # will arrive and the transfer can be parallelized.
    274 #
    275 # With slow disks and fast (large bandwidth) networks, diskless replication
    276 # works better.
    277 repl-diskless-sync no
    278 
    279 # When diskless replication is enabled, it is possible to configure the delay
    280 # the server waits in order to spawn the child that transfers the RDB via socket
    281 # to the slaves.
    282 #
    283 # This is important since once the transfer starts, it is not possible to serve
    284 # new slaves arriving, that will be queued for the next RDB transfer, so the server
    285 # waits a delay in order to let more slaves arrive.
    286 #
    287 # The delay is specified in seconds, and by default is 5 seconds. To disable
    288 # it entirely just set it to 0 seconds and the transfer will start ASAP.
    289 repl-diskless-sync-delay 5
    290 
    291 # Slaves send PINGs to server in a predefined interval. It's possible to change
    292 # this interval with the repl_ping_slave_period option. The default value is 10
    293 # seconds.
    294 #
    295 # repl-ping-slave-period 10
    296 
    297 # The following option sets the replication timeout for:
    298 #
    299 # 1) Bulk transfer I/O during SYNC, from the point of view of slave.
    300 # 2) Master timeout from the point of view of slaves (data, pings).
    301 # 3) Slave timeout from the point of view of masters (REPLCONF ACK pings).
    302 #
    303 # It is important to make sure that this value is greater than the value
    304 # specified for repl-ping-slave-period otherwise a timeout will be detected
    305 # every time there is low traffic between the master and the slave.
    306 #
    307 # repl-timeout 60
    308 
    309 # Disable TCP_NODELAY on the slave socket after SYNC?
    310 #
    311 # If you select "yes" Redis will use a smaller number of TCP packets and
    312 # less bandwidth to send data to slaves. But this can add a delay for
    313 # the data to appear on the slave side, up to 40 milliseconds with
    314 # Linux kernels using a default configuration.
    315 #
    316 # If you select "no" the delay for data to appear on the slave side will
    317 # be reduced but more bandwidth will be used for replication.
    318 #
    319 # By default we optimize for low latency, but in very high traffic conditions
    320 # or when the master and slaves are many hops away, turning this to "yes" may
    321 # be a good idea.
    322 repl-disable-tcp-nodelay no
    323 
    324 # Set the replication backlog size. The backlog is a buffer that accumulates
    325 # slave data when slaves are disconnected for some time, so that when a slave
    326 # wants to reconnect again, often a full resync is not needed, but a partial
    327 # resync is enough, just passing the portion of data the slave missed while
    328 # disconnected.
    329 #
    330 # The bigger the replication backlog, the longer the time the slave can be
    331 # disconnected and later be able to perform a partial resynchronization.
    332 #
    333 # The backlog is only allocated once there is at least a slave connected.
    334 #
    335 # repl-backlog-size 1mb
    336 
    337 # After a master has no longer connected slaves for some time, the backlog
    338 # will be freed. The following option configures the amount of seconds that
    339 # need to elapse, starting from the time the last slave disconnected, for
    340 # the backlog buffer to be freed.
    341 #
    342 # A value of 0 means to never release the backlog.
    343 #
    344 # repl-backlog-ttl 3600
    345 
    346 # The slave priority is an integer number published by Redis in the INFO output.
    347 # It is used by Redis Sentinel in order to select a slave to promote into a
    348 # master if the master is no longer working correctly.
    349 #
    350 # A slave with a low priority number is considered better for promotion, so
    351 # for instance if there are three slaves with priority 10, 100, 25 Sentinel will
    352 # pick the one with priority 10, that is the lowest.
    353 #
    354 # However a special priority of 0 marks the slave as not able to perform the
    355 # role of master, so a slave with priority of 0 will never be selected by
    356 # Redis Sentinel for promotion.
    357 #
    358 # By default the priority is 100.
    359 slave-priority 100
    360 
    361 # It is possible for a master to stop accepting writes if there are less than
    362 # N slaves connected, having a lag less or equal than M seconds.
    363 #
    364 # The N slaves need to be in "online" state.
    365 #
    366 # The lag in seconds, that must be <= the specified value, is calculated from
    367 # the last ping received from the slave, that is usually sent every second.
    368 #
    369 # This option does not GUARANTEE that N replicas will accept the write, but
    370 # will limit the window of exposure for lost writes in case not enough slaves
    371 # are available, to the specified number of seconds.
    372 #
    373 # For example to require at least 3 slaves with a lag <= 10 seconds use:
    374 #
    375 # min-slaves-to-write 3
    376 # min-slaves-max-lag 10
    377 #
    378 # Setting one or the other to 0 disables the feature.
    379 #
    380 # By default min-slaves-to-write is set to 0 (feature disabled) and
    381 # min-slaves-max-lag is set to 10.
    382 
    383 ################################## SECURITY ###################################
    384 
    385 # Require clients to issue AUTH <PASSWORD> before processing any other
    386 # commands.  This might be useful in environments in which you do not trust
    387 # others with access to the host running redis-server.
    388 #
    389 # This should stay commented out for backward compatibility and because most
    390 # people do not need auth (e.g. they run their own servers).
    391 #
    392 # Warning: since Redis is pretty fast an outside user can try up to
    393 # 150k passwords per second against a good box. This means that you should
    394 # use a very strong password otherwise it will be very easy to break.
    395 #
    396 # requirepass foobared
    397 
    398 # Command renaming.
    399 #
    400 # It is possible to change the name of dangerous commands in a shared
    401 # environment. For instance the CONFIG command may be renamed into something
    402 # hard to guess so that it will still be available for internal-use tools
    403 # but not available for general clients.
    404 #
    405 # Example:
    406 #
    407 # rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
    408 #
    409 # It is also possible to completely kill a command by renaming it into
    410 # an empty string:
    411 #
    412 # rename-command CONFIG ""
    413 #
    414 # Please note that changing the name of commands that are logged into the
    415 # AOF file or transmitted to slaves may cause problems.
    416 
    417 ################################### LIMITS ####################################
    418 
    419 # Set the max number of connected clients at the same time. By default
    420 # this limit is set to 10000 clients, however if the Redis server is not
    421 # able to configure the process file limit to allow for the specified limit
    422 # the max number of allowed clients is set to the current file limit
    423 # minus 32 (as Redis reserves a few file descriptors for internal uses).
    424 #
    425 # Once the limit is reached Redis will close all the new connections sending
    426 # an error 'max number of clients reached'.
    427 #
    428 # maxclients 10000
    429 
    430 # Don't use more memory than the specified amount of bytes.
    431 # When the memory limit is reached Redis will try to remove keys
    432 # according to the eviction policy selected (see maxmemory-policy).
    433 #
    434 # If Redis can't remove keys according to the policy, or if the policy is
    435 # set to 'noeviction', Redis will start to reply with errors to commands
    436 # that would use more memory, like SET, LPUSH, and so on, and will continue
    437 # to reply to read-only commands like GET.
    438 #
    439 # This option is usually useful when using Redis as an LRU cache, or to set
    440 # a hard memory limit for an instance (using the 'noeviction' policy).
    441 #
    442 # WARNING: If you have slaves attached to an instance with maxmemory on,
    443 # the size of the output buffers needed to feed the slaves are subtracted
    444 # from the used memory count, so that network problems / resyncs will
    445 # not trigger a loop where keys are evicted, and in turn the output
    446 # buffer of slaves is full with DELs of keys evicted triggering the deletion
    447 # of more keys, and so forth until the database is completely emptied.
    448 #
    449 # In short... if you have slaves attached it is suggested that you set a lower
    450 # limit for maxmemory so that there is some free RAM on the system for slave
    451 # output buffers (but this is not needed if the policy is 'noeviction').
    452 #
    453 # maxmemory <bytes>
    454 
    455 # MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
    456 # is reached. You can select among five behaviors:
    457 #
    458 # volatile-lru -> remove the key with an expire set using an LRU algorithm
    459 # allkeys-lru -> remove any key according to the LRU algorithm
    460 # volatile-random -> remove a random key with an expire set
    461 # allkeys-random -> remove a random key, any key
    462 # volatile-ttl -> remove the key with the nearest expire time (minor TTL)
    463 # noeviction -> don't expire at all, just return an error on write operations
    464 #
    465 # Note: with any of the above policies, Redis will return an error on write
    466 #       operations, when there are no suitable keys for eviction.
    467 #
    468 #       At the date of writing these commands are: set setnx setex append
    469 #       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
    470 #       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
    471 #       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
    472 #       getset mset msetnx exec sort
    473 #
    474 # The default is:
    475 #
    476 # maxmemory-policy noeviction
    477 
    478 # LRU and minimal TTL algorithms are not precise algorithms but approximated
    479 # algorithms (in order to save memory), so you can tune it for speed or
    480 # accuracy. For default Redis will check five keys and pick the one that was
    481 # used less recently, you can change the sample size using the following
    482 # configuration directive.
    483 #
    484 # The default of 5 produces good enough results. 10 Approximates very closely
    485 # true LRU but costs a bit more CPU. 3 is very fast but not very accurate.
    486 #
    487 # maxmemory-samples 5
    488 
    489 ############################## APPEND ONLY MODE ###############################
    490 
    491 # By default Redis asynchronously dumps the dataset on disk. This mode is
    492 # good enough in many applications, but an issue with the Redis process or
    493 # a power outage may result into a few minutes of writes lost (depending on
    494 # the configured save points).
    495 #
    496 # The Append Only File is an alternative persistence mode that provides
    497 # much better durability. For instance using the default data fsync policy
    498 # (see later in the config file) Redis can lose just one second of writes in a
    499 # dramatic event like a server power outage, or a single write if something
    500 # wrong with the Redis process itself happens, but the operating system is
    501 # still running correctly.
    502 #
    503 # AOF and RDB persistence can be enabled at the same time without problems.
    504 # If the AOF is enabled on startup Redis will load the AOF, that is the file
    505 # with the better durability guarantees.
    506 #
    507 # Please check http://redis.io/topics/persistence for more information.
    508 
    509 appendonly no
    510 
    511 # The name of the append only file (default: "appendonly.aof")
    512 
    513 appendfilename "appendonly.aof"
    514 
    515 # The fsync() call tells the Operating System to actually write data on disk
    516 # instead of waiting for more data in the output buffer. Some OS will really flush
    517 # data on disk, some other OS will just try to do it ASAP.
    518 #
    519 # Redis supports three different modes:
    520 #
    521 # no: don't fsync, just let the OS flush the data when it wants. Faster.
    522 # always: fsync after every write to the append only log. Slow, Safest.
    523 # everysec: fsync only one time every second. Compromise.
    524 #
    525 # The default is "everysec", as that's usually the right compromise between
    526 # speed and data safety. It's up to you to understand if you can relax this to
    527 # "no" that will let the operating system flush the output buffer when
    528 # it wants, for better performances (but if you can live with the idea of
    529 # some data loss consider the default persistence mode that's snapshotting),
    530 # or on the contrary, use "always" that's very slow but a bit safer than
    531 # everysec.
    532 #
    533 # More details please check the following article:
    534 # http://antirez.com/post/redis-persistence-demystified.html
    535 #
    536 # If unsure, use "everysec".
    537 
    538 # appendfsync always
    539 appendfsync everysec
    540 # appendfsync no
    541 
    542 # When the AOF fsync policy is set to always or everysec, and a background
    543 # saving process (a background save or AOF log background rewriting) is
    544 # performing a lot of I/O against the disk, in some Linux configurations
    545 # Redis may block too long on the fsync() call. Note that there is no fix for
    546 # this currently, as even performing fsync in a different thread will block
    547 # our synchronous write(2) call.
    548 #
    549 # In order to mitigate this problem it's possible to use the following option
    550 # that will prevent fsync() from being called in the main process while a
    551 # BGSAVE or BGREWRITEAOF is in progress.
    552 #
    553 # This means that while another child is saving, the durability of Redis is
    554 # the same as "appendfsync none". In practical terms, this means that it is
    555 # possible to lose up to 30 seconds of log in the worst scenario (with the
    556 # default Linux settings).
    557 #
    558 # If you have latency problems turn this to "yes". Otherwise leave it as
    559 # "no" that is the safest pick from the point of view of durability.
    560 
    561 no-appendfsync-on-rewrite no
    562 
    563 # Automatic rewrite of the append only file.
    564 # Redis is able to automatically rewrite the log file implicitly calling
    565 # BGREWRITEAOF when the AOF log size grows by the specified percentage.
    566 #
    567 # This is how it works: Redis remembers the size of the AOF file after the
    568 # latest rewrite (if no rewrite has happened since the restart, the size of
    569 # the AOF at startup is used).
    570 #
    571 # This base size is compared to the current size. If the current size is
    572 # bigger than the specified percentage, the rewrite is triggered. Also
    573 # you need to specify a minimal size for the AOF file to be rewritten, this
    574 # is useful to avoid rewriting the AOF file even if the percentage increase
    575 # is reached but it is still pretty small.
    576 #
    577 # Specify a percentage of zero in order to disable the automatic AOF
    578 # rewrite feature.
    579 
    580 auto-aof-rewrite-percentage 100
    581 auto-aof-rewrite-min-size 64mb
    582 
    583 # An AOF file may be found to be truncated at the end during the Redis
    584 # startup process, when the AOF data gets loaded back into memory.
    585 # This may happen when the system where Redis is running
    586 # crashes, especially when an ext4 filesystem is mounted without the
    587 # data=ordered option (however this can't happen when Redis itself
    588 # crashes or aborts but the operating system still works correctly).
    589 #
    590 # Redis can either exit with an error when this happens, or load as much
    591 # data as possible (the default now) and start if the AOF file is found
    592 # to be truncated at the end. The following option controls this behavior.
    593 #
    594 # If aof-load-truncated is set to yes, a truncated AOF file is loaded and
    595 # the Redis server starts emitting a log to inform the user of the event.
    596 # Otherwise if the option is set to no, the server aborts with an error
    597 # and refuses to start. When the option is set to no, the user requires
    598 # to fix the AOF file using the "redis-check-aof" utility before to restart
    599 # the server.
    600 #
    601 # Note that if the AOF file will be found to be corrupted in the middle
    602 # the server will still exit with an error. This option only applies when
    603 # Redis will try to read more data from the AOF file but not enough bytes
    604 # will be found.
    605 aof-load-truncated yes
    606 
    607 ################################ LUA SCRIPTING  ###############################
    608 
    609 # Max execution time of a Lua script in milliseconds.
    610 #
    611 # If the maximum execution time is reached Redis will log that a script is
    612 # still in execution after the maximum allowed time and will start to
    613 # reply to queries with an error.
    614 #
    615 # When a long running script exceeds the maximum execution time only the
    616 # SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
    617 # used to stop a script that did not yet called write commands. The second
    618 # is the only way to shut down the server in the case a write command was
    619 # already issued by the script but the user doesn't want to wait for the natural
    620 # termination of the script.
    621 #
    622 # Set it to 0 or a negative value for unlimited execution without warnings.
    623 lua-time-limit 5000
    624 
    625 ################################ REDIS CLUSTER  ###############################
    626 #
    627 # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    628 # WARNING EXPERIMENTAL: Redis Cluster is considered to be stable code, however
    629 # in order to mark it as "mature" we need to wait for a non trivial percentage
    630 # of users to deploy it in production.
    631 # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    632 #
    633 # Normal Redis instances can't be part of a Redis Cluster; only nodes that are
    634 # started as cluster nodes can. In order to start a Redis instance as a
    635 # cluster node enable the cluster support uncommenting the following:
    636 #
    637 # cluster-enabled yes
    638 
    639 # Every cluster node has a cluster configuration file. This file is not
    640 # intended to be edited by hand. It is created and updated by Redis nodes.
    641 # Every Redis Cluster node requires a different cluster configuration file.
    642 # Make sure that instances running in the same system do not have
    643 # overlapping cluster configuration file names.
    644 #
    645 # cluster-config-file nodes-6379.conf
    646 
    647 # Cluster node timeout is the amount of milliseconds a node must be unreachable
    648 # for it to be considered in failure state.
    649 # Most other internal time limits are multiple of the node timeout.
    650 #
    651 # cluster-node-timeout 15000
    652 
    653 # A slave of a failing master will avoid to start a failover if its data
    654 # looks too old.
    655 #
    656 # There is no simple way for a slave to actually have a exact measure of
    657 # its "data age", so the following two checks are performed:
    658 #
    659 # 1) If there are multiple slaves able to failover, they exchange messages
    660 #    in order to try to give an advantage to the slave with the best
    661 #    replication offset (more data from the master processed).
    662 #    Slaves will try to get their rank by offset, and apply to the start
    663 #    of the failover a delay proportional to their rank.
    664 #
    665 # 2) Every single slave computes the time of the last interaction with
    666 #    its master. This can be the last ping or command received (if the master
    667 #    is still in the "connected" state), or the time that elapsed since the
    668 #    disconnection with the master (if the replication link is currently down).
    669 #    If the last interaction is too old, the slave will not try to failover
    670 #    at all.
    671 #
    672 # The point "2" can be tuned by user. Specifically a slave will not perform
    673 # the failover if, since the last interaction with the master, the time
    674 # elapsed is greater than:
    675 #
    676 #   (node-timeout * slave-validity-factor) + repl-ping-slave-period
    677 #
    678 # So for example if node-timeout is 30 seconds, and the slave-validity-factor
    679 # is 10, and assuming a default repl-ping-slave-period of 10 seconds, the
    680 # slave will not try to failover if it was not able to talk with the master
    681 # for longer than 310 seconds.
    682 #
    683 # A large slave-validity-factor may allow slaves with too old data to failover
    684 # a master, while a too small value may prevent the cluster from being able to
    685 # elect a slave at all.
    686 #
    687 # For maximum availability, it is possible to set the slave-validity-factor
    688 # to a value of 0, which means, that slaves will always try to failover the
    689 # master regardless of the last time they interacted with the master.
    690 # (However they'll always try to apply a delay proportional to their
    691 # offset rank).
    692 #
    693 # Zero is the only value able to guarantee that when all the partitions heal
    694 # the cluster will always be able to continue.
    695 #
    696 # cluster-slave-validity-factor 10
    697 
    698 # Cluster slaves are able to migrate to orphaned masters, that are masters
    699 # that are left without working slaves. This improves the cluster ability
    700 # to resist to failures as otherwise an orphaned master can't be failed over
    701 # in case of failure if it has no working slaves.
    702 #
    703 # Slaves migrate to orphaned masters only if there are still at least a
    704 # given number of other working slaves for their old master. This number
    705 # is the "migration barrier". A migration barrier of 1 means that a slave
    706 # will migrate only if there is at least 1 other working slave for its master
    707 # and so forth. It usually reflects the number of slaves you want for every
    708 # master in your cluster.
    709 #
    710 # Default is 1 (slaves migrate only if their masters remain with at least
    711 # one slave). To disable migration just set it to a very large value.
    712 # A value of 0 can be set but is useful only for debugging and dangerous
    713 # in production.
    714 #
    715 # cluster-migration-barrier 1
    716 
    717 # By default Redis Cluster nodes stop accepting queries if they detect there
    718 # is at least an hash slot uncovered (no available node is serving it).
    719 # This way if the cluster is partially down (for example a range of hash slots
    720 # are no longer covered) all the cluster becomes, eventually, unavailable.
    721 # It automatically returns available as soon as all the slots are covered again.
    722 #
    723 # However sometimes you want the subset of the cluster which is working,
    724 # to continue to accept queries for the part of the key space that is still
    725 # covered. In order to do so, just set the cluster-require-full-coverage
    726 # option to no.
    727 #
    728 # cluster-require-full-coverage yes
    729 
    730 # In order to setup your cluster make sure to read the documentation
    731 # available at http://redis.io web site.
    732 
    733 ################################## SLOW LOG ###################################
    734 
    735 # The Redis Slow Log is a system to log queries that exceeded a specified
    736 # execution time. The execution time does not include the I/O operations
    737 # like talking with the client, sending the reply and so forth,
    738 # but just the time needed to actually execute the command (this is the only
    739 # stage of command execution where the thread is blocked and can not serve
    740 # other requests in the meantime).
    741 #
    742 # You can configure the slow log with two parameters: one tells Redis
    743 # what is the execution time, in microseconds, to exceed in order for the
    744 # command to get logged, and the other parameter is the length of the
    745 # slow log. When a new command is logged the oldest one is removed from the
    746 # queue of logged commands.
    747 
    748 # The following time is expressed in microseconds, so 1000000 is equivalent
    749 # to one second. Note that a negative number disables the slow log, while
    750 # a value of zero forces the logging of every command.
    751 slowlog-log-slower-than 10000
    752 
    753 # There is no limit to this length. Just be aware that it will consume memory.
    754 # You can reclaim memory used by the slow log with SLOWLOG RESET.
    755 slowlog-max-len 128
    756 
    757 ################################ LATENCY MONITOR ##############################
    758 
    759 # The Redis latency monitoring subsystem samples different operations
    760 # at runtime in order to collect data related to possible sources of
    761 # latency of a Redis instance.
    762 #
    763 # Via the LATENCY command this information is available to the user that can
    764 # print graphs and obtain reports.
    765 #
    766 # The system only logs operations that were performed in a time equal or
    767 # greater than the amount of milliseconds specified via the
    768 # latency-monitor-threshold configuration directive. When its value is set
    769 # to zero, the latency monitor is turned off.
    770 #
    771 # By default latency monitoring is disabled since it is mostly not needed
    772 # if you don't have latency issues, and collecting data has a performance
    773 # impact, that while very small, can be measured under big load. Latency
    774 # monitoring can easily be enabled at runtime using the command
    775 # "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
    776 latency-monitor-threshold 0
    777 
    778 ############################# EVENT NOTIFICATION ##############################
    779 
    780 # Redis can notify Pub/Sub clients about events happening in the key space.
    781 # This feature is documented at http://redis.io/topics/notifications
    782 #
    783 # For instance if keyspace events notification is enabled, and a client
    784 # performs a DEL operation on key "foo" stored in the Database 0, two
    785 # messages will be published via Pub/Sub:
    786 #
    787 # PUBLISH __keyspace@0__:foo del
    788 # PUBLISH __keyevent@0__:del foo
    789 #
    790 # It is possible to select the events that Redis will notify among a set
    791 # of classes. Every class is identified by a single character:
    792 #
    793 #  K     Keyspace events, published with __keyspace@<db>__ prefix.
    794 #  E     Keyevent events, published with __keyevent@<db>__ prefix.
    795 #  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
    796 #  $     String commands
    797 #  l     List commands
    798 #  s     Set commands
    799 #  h     Hash commands
    800 #  z     Sorted set commands
    801 #  x     Expired events (events generated every time a key expires)
    802 #  e     Evicted events (events generated when a key is evicted for maxmemory)
    803 #  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
    804 #
    805 #  The "notify-keyspace-events" takes as argument a string that is composed
    806 #  of zero or multiple characters. The empty string means that notifications
    807 #  are disabled.
    808 #
    809 #  Example: to enable list and generic events, from the point of view of the
    810 #           event name, use:
    811 #
    812 #  notify-keyspace-events Elg
    813 #
    814 #  Example 2: to get the stream of the expired keys subscribing to channel
    815 #             name __keyevent@0__:expired use:
    816 #
    817 #  notify-keyspace-events Ex
    818 #
    819 #  By default all notifications are disabled because most users don't need
    820 #  this feature and the feature has some overhead. Note that if you don't
    821 #  specify at least one of K or E, no events will be delivered.
    822 notify-keyspace-events ""
    823 
    824 ############################### ADVANCED CONFIG ###############################
    825 
    826 # Hashes are encoded using a memory efficient data structure when they have a
    827 # small number of entries, and the biggest entry does not exceed a given
    828 # threshold. These thresholds can be configured using the following directives.
    829 hash-max-ziplist-entries 512
    830 hash-max-ziplist-value 64
    831 
    832 # Similarly to hashes, small lists are also encoded in a special way in order
    833 # to save a lot of space. The special representation is only used when
    834 # you are under the following limits:
    835 list-max-ziplist-entries 512
    836 list-max-ziplist-value 64
    837 
    838 # Sets have a special encoding in just one case: when a set is composed
    839 # of just strings that happen to be integers in radix 10 in the range
    840 # of 64 bit signed integers.
    841 # The following configuration setting sets the limit in the size of the
    842 # set in order to use this special memory saving encoding.
    843 set-max-intset-entries 512
    844 
    845 # Similarly to hashes and lists, sorted sets are also specially encoded in
    846 # order to save a lot of space. This encoding is only used when the length and
    847 # elements of a sorted set are below the following limits:
    848 zset-max-ziplist-entries 128
    849 zset-max-ziplist-value 64
    850 
    851 # HyperLogLog sparse representation bytes limit. The limit includes the
    852 # 16 bytes header. When an HyperLogLog using the sparse representation crosses
    853 # this limit, it is converted into the dense representation.
    854 #
    855 # A value greater than 16000 is totally useless, since at that point the
    856 # dense representation is more memory efficient.
    857 #
    858 # The suggested value is ~ 3000 in order to have the benefits of
    859 # the space efficient encoding without slowing down too much PFADD,
    860 # which is O(N) with the sparse encoding. The value can be raised to
    861 # ~ 10000 when CPU is not a concern, but space is, and the data set is
    862 # composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
    863 hll-sparse-max-bytes 3000
    864 
    865 # Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
    866 # order to help rehashing the main Redis hash table (the one mapping top-level
    867 # keys to values). The hash table implementation Redis uses (see dict.c)
    868 # performs a lazy rehashing: the more operation you run into a hash table
    869 # that is rehashing, the more rehashing "steps" are performed, so if the
    870 # server is idle the rehashing is never complete and some more memory is used
    871 # by the hash table.
    872 #
    873 # The default is to use this millisecond 10 times every second in order to
    874 # actively rehash the main dictionaries, freeing memory when possible.
    875 #
    876 # If unsure:
    877 # use "activerehashing no" if you have hard latency requirements and it is
    878 # not a good thing in your environment that Redis can reply from time to time
    879 # to queries with 2 milliseconds delay.
    880 #
    881 # use "activerehashing yes" if you don't have such hard requirements but
    882 # want to free memory asap when possible.
    883 activerehashing yes
    884 
    885 # The client output buffer limits can be used to force disconnection of clients
    886 # that are not reading data from the server fast enough for some reason (a
    887 # common reason is that a Pub/Sub client can't consume messages as fast as the
    888 # publisher can produce them).
    889 #
    890 # The limit can be set differently for the three different classes of clients:
    891 #
    892 # normal -> normal clients including MONITOR clients
    893 # slave  -> slave clients
    894 # pubsub -> clients subscribed to at least one pubsub channel or pattern
    895 #
    896 # The syntax of every client-output-buffer-limit directive is the following:
    897 #
    898 # client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
    899 #
    900 # A client is immediately disconnected once the hard limit is reached, or if
    901 # the soft limit is reached and remains reached for the specified number of
    902 # seconds (continuously).
    903 # So for instance if the hard limit is 32 megabytes and the soft limit is
    904 # 16 megabytes / 10 seconds, the client will get disconnected immediately
    905 # if the size of the output buffers reach 32 megabytes, but will also get
    906 # disconnected if the client reaches 16 megabytes and continuously overcomes
    907 # the limit for 10 seconds.
    908 #
    909 # By default normal clients are not limited because they don't receive data
    910 # without asking (in a push way), but just after a request, so only
    911 # asynchronous clients may create a scenario where data is requested faster
    912 # than it can read.
    913 #
    914 # Instead there is a default limit for pubsub and slave clients, since
    915 # subscribers and slaves receive data in a push fashion.
    916 #
    917 # Both the hard or the soft limit can be disabled by setting them to zero.
    918 client-output-buffer-limit normal 0 0 0
    919 client-output-buffer-limit slave 256mb 64mb 60
    920 client-output-buffer-limit pubsub 32mb 8mb 60
    921 
    922 # Redis calls an internal function to perform many background tasks, like
    923 # closing connections of clients in timeout, purging expired keys that are
    924 # never requested, and so forth.
    925 #
    926 # Not all tasks are performed with the same frequency, but Redis checks for
    927 # tasks to perform according to the specified "hz" value.
    928 #
    929 # By default "hz" is set to 10. Raising the value will use more CPU when
    930 # Redis is idle, but at the same time will make Redis more responsive when
    931 # there are many keys expiring at the same time, and timeouts may be
    932 # handled with more precision.
    933 #
    934 # The range is between 1 and 500, however a value over 100 is usually not
    935 # a good idea. Most users should use the default of 10 and raise this up to
    936 # 100 only in environments where very low latency is required.
    937 hz 10
    938 
    939 # When a child rewrites the AOF file, if the following option is enabled
    940 # the file will be fsync-ed every 32 MB of data generated. This is useful
    941 # in order to commit the file to the disk more incrementally and avoid
    942 # big latency spikes.
    943 aof-rewrite-incremental-fsync yes
    redis.conf

    有问题请留言,暂时先写这么多。

    ------ 往事如烟,伴着远去的步伐而愈加朦胧。未来似雾,和着前进的风儿而逐渐清晰!
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  • 原文地址:https://www.cnblogs.com/cutesnow/p/6866854.html
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