Linux系统安装MongoDB数据库步骤

MongoDB安装比较简单，centos可以直接用yum或rpm包安装，ubuntu或debian可以直接用apt或deb包安装。不过个人还是习惯直接下载官方源码或二进制文件安装。以下我就从官方下载安装文件安装，步骤类似如下。

1、修改主机名，添加hosts信息

echo "mongodb1" >/etc/hostname
hostname mongodb1      

修改添加/etc/hosts，例如：

192.168.1.106       mongodb1      

2、创建mongo用户和数据目录

useradd mongo
mkdir -pv /data/mongodb
chown -R mongo.mongo /data/mongodb
chmod go-rwx /data/mongodb      

3、下载安装

下载的是3.2的最新版本。

mkdir /root/softbak
cd /root/softbak
wget https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.2.21.tgz
tar zxf mongodb-linux-x86_64-3.2.21.tgz
mv mongodb-linux-x86_64-3.2.21 /usr/local/mongodb      

增加环境变量

vim /etc/profile
export PATH=/usr/local/mongodb/bin:$PATH
source /etc/profile      

配置目录

mkdir /usr/local/mongodb/etc
chown mongo.mongo /usr/local/mongodb/etc
chmod go-rwx /usr/local/mongodb/etc      

4、配置启动

su - root
mkdir -pv /var/log/mongodb
mkdir -pv /var/run/mongodb
chown -R mongo.mongo /var/log/mongodb/
chown -R mongo.mongo /var/run/mongodb/      

关闭hugepage的动态分配，默认centos 7开启。

参考：https://docs.mongodb.com/manual/tutorial/transparent-huge-pages/

vim /etc/init.d/disable-transparent-hugepages
#!/bin/bash
### BEGIN INIT INFO
# Provides:          disable-transparent-hugepages
# Required-Start:    $local_fs
# Required-Stop:
# X-Start-Before:    mongod mongodb-mms-automation-agent
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Disable Linux transparent huge pages
# Description:       Disable Linux transparent huge pages, to improve
#                    database performance.
### END INIT INFO
  
case $1 in
  start)
    if [ -d /sys/kernel/mm/transparent_hugepage ]; then
      thp_path=/sys/kernel/mm/transparent_hugepage
    elif [ -d /sys/kernel/mm/redhat_transparent_hugepage ]; then
      thp_path=/sys/kernel/mm/redhat_transparent_hugepage
    else
      return 0
    fi
  
    echo 'never' > ${thp_path}/enabled
    echo 'never' > ${thp_path}/defrag
  
    re='^[0-1]+$'
    if [[ $(cat ${thp_path}/khugepaged/defrag) =~ $re ]]
    then
      # RHEL 7
      echo 0  > ${thp_path}/khugepaged/defrag
    else
      # RHEL 6
      echo 'no' > ${thp_path}/khugepaged/defrag
    fi
  
    unset re
    unset thp_path
    ;;
esac      

添加开机自动启动

chmod 755 /etc/init.d/disable-transparent-hugepages
chkconfig --add disable-transparent-hugepages      

修改ulimit限制

参考：https://docs.mongodb.com/manual/reference/ulimit/

默认需要修改的地方是open files、nproc和lock in memory size。

vim /etc/security/limits.conf
 
# 推荐配置如下
-f (file size): unlimited
-t (cpu time): unlimited
-v (virtual memory): unlimited
-l (locked-in-memory size): unlimited
-n (open files): 64000
-m (memory size): unlimited
-u (processes/threads): 64000      

配置类似如下

su - mongo
cd /usr/local/mongodb/etc
  
cat /usr/local/mongodb/etc/mongod.conf
systemLog:
  destination: file
  logAppend: true
  path: /var/log/mongodb/mongod.log
  
storage:
  dbPath: /data/mongodb
  journal:
    enabled: true
  
processManagement:
  fork: true
  pidFilePath: /var/run/mongodb/mongod.pid
  
replication:
  replSetName: rs1
  
net:
  port: 27017
  bindIp: 0.0.0.0      

su - mongo
mongod -f /usr/local/mongodb/etc/mongod.conf      

su - mongo
mongo