1. 安装环境准备

1.1 主机环境准备

1.1.1. 关闭selinux

sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
setenforce 0

1.1.2. 软件下载

下载版本：memcached-1.6.6.tar.gz

下载地址：
http://memcached.org/downloads

1.1.3. 部署规划

软件安装路径：/usr/local/memcache

端口规划：11222

1.1.4. 系统主机时间、时区、系统语言

l 本节视实际情况需要操作

l 修改时区

ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

l 修改系统语言环境

echo 'LANG="en_US.UTF-8"' >> /etc/profile && source /etc/profile

l 配置主机NTP时间同步

yum -y install ntp
systemctl enable ntpd && systemctl start ntpd
echo 'server ntp1.aliyun.com' >> /etc/ntp.conf
echo 'server ntp2.aliyun.com' >> /etc/ntp.conf

2. Memcached安装部署

2.1 Memcached依赖安装及部署

l 添加用户与用户组（用户名请自行定义）

groupadd -r middleware && useradd -s /sbin/nologin -r -M -g middleware middleware

l 下载memcached-1.6.6.tar.gz安装包，并解压安装

yum -y install gcc gcc-c++ automake autoconf libevent-devel libevent make wget
cd /opt
wget http://memcached.org/files/memcached-1.6.6.tar.gz
tar -zxvf memcached-1.6.6.tar.gz
cd memcached-1.6.6
./configure --prefix=/usr/local/memcached
make && make install

l Memcached启动命令

/usr/local/memcached/bin/memcached -d -l 127.0.0.1 -m 256 -u middleware -p 11222 -c 1024 -P /var/run/memcached.pid

l Memcached启动选项简介

-d是启动一个守护进程；

-m是分配给Memcached使用的内存数量，单位是MB；

-u是运行Memcached的用户；

-l是监听的服务器IP地址，可以有多个地址；

-p是设置Memcached监听的端口，，最好是1024以上的端口；

-c是最大运行的并发连接数，默认是1024；

-P是设置保存Memcached的pid文件。

2.2 配置memcached系统服务

2.2.1. 针对6系统添加系统服务

1、添加防火墙策略

（1）所有机器可访问

iptables -A INPUT -p tcp --dport 11222 -j ACCEPT
service iptables save

（2）特定IP192.168.142.166可访问本机11222端口

iptables -A INPUT -p tcp -s 192.168.142.166 --dport 11222 -j ACCEPT
service iptables save

2、添加memcached系统服务启动脚本

vi /etc/init.d/memcached
#!/bin/bash
#
# memcached     start/stop the memcached daemon
#
# chkconfig: 345 81 19
# description: memcached is a memory cache server.
#
 
prog="memcached"
exec=/usr/local/memcached/bin/memcached
CMD="$exec -u middleware -d -m 256 -p 11222 -c 1024 -P /tmp/memcached.pid"
lockfile=/var/lock/subsys/memcached
PID=`ps -ef|grep -v grep |grep memcached |awk '{print $2}'`
# source function library.
. /etc/rc.d/init.d/functions
 
start() {
    if [ $UID -ne 0 ]; then
        echo "User has insufficient privilege."
        exit 4
    fi
    [ -x $exec ] || exit 5
    echo -n $"starting $prog: "
    daemon $CMD
    retval=$?
    echo
    [ $retval -eq 0 ] && touch $lockfile
}
 
stop() {
    if [ $UID -ne 0 ]; then
        echo "User has insufficient privilege."
        exit 4
    fi
    kill -9 $PID
  retval=$?
    echo -n $"Stopping $prog: "
        if [ $retval -ne 0 ]; then
           failure $"stopping $prog"
        else
           echo
             [ $retval -eq 0 ] && rm -f $lockfile
        fi
}
 
restart() {
    stop
    start
}
 
rh_status() {
    # run checks to determine if the service is running or use generic status
    status $prog
}
 
rh_status_q() {
    rh_status >/dev/null 2>&1
}
 
case "$1" in
    "start")
        rh_status_q && exit 0
        $1
        ;;
    "stop")
        rh_status_q || exit 0
        $1
        ;;
    "restart")
        rh_status_q || exit 7
        $1
        ;;
    "status")
        rh_status
        ;;
    *)
        echo $"Usage: $0 {start|stop|status|restart}"
        exit 2
        ;;
esac
exit $?

2、配置memcached系统服务及自启动

chmod +x /etc/init.d/memcached
chkconfig --add memcached && chkconfig memcached on
chkconfig --list memcached

3、启动与停止memcached服务

service memcached start
ps -ef|grep memcached
service memcached stop

2.2.2. 针对7系统添加系统服务

1、添加防火墙策略

（1）所有机器可访问

firewall-cmd --permanent --zone=public --add-port=11222/tcp
firewall-cmd --reload

（2）特定IP192.168.142.166可访问本机11222端口

firewall-cmd --permanent --add-rich-rule="rule family="ipv4" source address="192.168.142.166" port protocol="tcp" port="11222" accept"
firewall-cmd --reload

（3）特定IP段192.168.142.0/24可访问本机11222端口

firewall-cmd --permanent --add-rich-rule="rule family="ipv4" source address="192.168.142.0/24" port protocol="tcp" port="11222" accept"
firewall-cmd --reload

2、添加memcached系统服务启动脚本

cat >/usr/lib/systemd/system/memcached.service<<EOF
[Unit]
Description=memcached
Requires=network-online.target
After=network.target
 
[Service]
Type=simple
ExecStart=/usr/local/memcached/bin/memcached -u middleware -l 127.0.0.1 -m 256 -p 11222 -c 1024 -P /tmp/memcached.pid
 
[Install]
WantedBy=multi-user.target
EOF

2、配置memcached系统服务及自启动

systemctl daemon-reload
systemctl enable memcached.service

3、启动与停止memcached服务

systemctl start memcached
ps -ef|grep memcached
systemctl stop memcached

3. Memcached加固

3.1 最小化权限用户启动

groupadd -r middleware && useradd -s /sbin/nologin -r -M -g middleware middleware
/usr/local/memcached/bin/memcached -d -l 127.0.0.1 -m 256 -u middleware -p 11222 -c 1024 -P /var/run/memcached.pid

3.2 禁止监听在公网

l Memcached启动时指定绑定的IP地址为 127.0.0.1。

/usr/local/memcached/bin/memcached -d -l 127.0.0.1 -m 256 -u middleware -p 11222 -c 1024 -P /var/run/memcached.pid

3.3 修改默认11211端口

l 默认情况下，memcached默认使用11211端口，请修改默认监听端口，如本文档使用的是11222

/usr/local/memcached/bin/memcached -d -l 127.0.0.1 -m 256 -u middleware -p 11222 -c 1024 -P /var/run/memcached.pid

3.4 定期升级

l 使用官方最新稳定版本

4. Memcached优化

4.1 优化内核参数

cat >>/etc/sysctl.conf<<EOF
fs.file-max = 6815744
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_fin_timeout = 30
net.ipv4.ip_local_port_range = 10000 65000
net.ipv4.tcp_max_syn_backlog = 8192
net.ipv4.tcp_max_tw_buckets = 10000
net.core.somaxconn=4000
net.ipv4.tcp_syncookies = 1
net.core.netdev_max_backlog = 262144
net.ipv4.tcp_max_orphans = 262144
EOF
sysctl -p

4.2 系统资源限制

cat >>/etc/security/limits.conf<<EOF
* soft nofile 65525
* hard nofile 65525
* soft nproc 65525
* hard nproc 65525
EOF

5. 结束