###当前环境
# cat /etc/issue
Red Hat Enterprise Linux Server release 6.5 (Santiago)

# vi /etc/selinux/config
SELINUX=disabled

下载地址： https://www.mongodb.org/downloads. 
或者直接在命令提示符下使用curl命令下载
curl -O https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.0.6.tgz

# pwd
/usr/local/src
# tar -xvf mongodb-linux-x86_64-rhel62-3.0.6.gz ###注，本文直接从网站下载，所以文件为.gz

# mkdir -p /var/lib/mongodb
# cp -R -n /usr/local/src/mongodb-linux-x86_64-rhel62-3.0.6/. /var/lib/mongodb/

e.g. export PATH=<mongodb-install-directory>/bin:$PATH
# vi ~/.bash_profile 
 export PATH=/var/lib/mongodb/bin:$PATH
# source ~/.bash_profile

# mkdir -p /data/mongodata

###启动mongo
# mongod --dbpath /data/mongodata

###以下内容为启动后输出的相关信息
2015-10-28T10:03:33.100+0800 I JOURNAL [initandlisten] journal dir=/data/mongodata/journal
2015-10-28T10:03:33.101+0800 I JOURNAL [initandlisten] recover : no journal files present, no recovery needed
2015-10-28T10:03:33.264+0800 I JOURNAL [initandlisten] preallocateIsFaster=true 2.18
2015-10-28T10:03:33.398+0800 I JOURNAL [durability] Durability thread started
2015-10-28T10:03:33.398+0800 I JOURNAL [journal writer] Journal writer thread started
2015-10-28T10:03:33.401+0800 I CONTROL [initandlisten] MongoDB starting : pid=10191 port=27017 dbpath=/data/mongodata 64-bit host=java_2
2015-10-28T10:03:33.401+0800 I CONTROL [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.
2015-10-28T10:03:33.401+0800 I CONTROL [initandlisten] 
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] 
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/enabled is 'always'.
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] **    We suggest setting it to 'never'
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] 
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/defrag is 'always'.
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] **    We suggest setting it to 'never'
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] 
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] db version v3.0.6
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] git version: 1ef45a23a4c5e3480ac919b28afcba3c615488f2
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] build info: Linux ip-10-67-194-123 2.6.32-220.el6.x86_64 #1 SMP Wed Nov 9 08:03:13 EST 2011 x86_64 BOOST_LIB_VERSION=1_49
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] allocator: tcmalloc
2015-10-28T10:03:33.402+0800 I CONTROL [initandlisten] options: { storage: { dbPath: "/data/mongodata" } }
2015-10-28T10:03:33.404+0800 I INDEX  [initandlisten] allocating new ns file /data/mongodata/local.ns, filling with zeroes...
2015-10-28T10:03:33.491+0800 I STORAGE [FileAllocator] allocating new datafile /data/mongodata/local.0, filling with zeroes...
2015-10-28T10:03:33.491+0800 I STORAGE [FileAllocator] creating directory /data/mongodata/_tmp
2015-10-28T10:03:33.497+0800 I STORAGE [FileAllocator] done allocating datafile /data/mongodata/local.0, size: 64MB, took 0.001 secs
2015-10-28T10:03:33.511+0800 I NETWORK [initandlisten] waiting for connections on port 27017

###停止mongo，直接使用ctrl + c
^C2015-10-28T10:09:21.510+0800 I CONTROL [signalProcessingThread] got signal 2 (Interrupt), will terminate after current cmd ends
2015-10-28T10:09:21.511+0800 I CONTROL [signalProcessingThread] now exiting
2015-10-28T10:09:21.511+0800 I NETWORK [signalProcessingThread] shutdown: going to close listening sockets...
2015-10-28T10:09:21.511+0800 I NETWORK [signalProcessingThread] closing listening socket: 5
2015-10-28T10:09:21.511+0800 I NETWORK [signalProcessingThread] closing listening socket: 6
2015-10-28T10:09:21.511+0800 I NETWORK [signalProcessingThread] removing socket file: /tmp/mongodb-27017.sock
2015-10-28T10:09:21.511+0800 I NETWORK [signalProcessingThread] shutdown: going to flush diaglog...
2015-10-28T10:09:21.511+0800 I NETWORK [signalProcessingThread] shutdown: going to close sockets...
2015-10-28T10:09:21.512+0800 I STORAGE [signalProcessingThread] shutdown: waiting for fs preallocator...
2015-10-28T10:09:21.512+0800 I STORAGE [signalProcessingThread] shutdown: final commit...
2015-10-28T10:09:21.512+0800 I JOURNAL [signalProcessingThread] journalCleanup...
2015-10-28T10:09:21.512+0800 I JOURNAL [signalProcessingThread] removeJournalFiles
2015-10-28T10:09:21.515+0800 I JOURNAL [signalProcessingThread] Terminating durability thread ...
2015-10-28T10:09:21.615+0800 I JOURNAL [journal writer] Journal writer thread stopped
2015-10-28T10:09:21.615+0800 I JOURNAL [durability] Durability thread stopped
2015-10-28T10:09:21.615+0800 I STORAGE [signalProcessingThread] shutdown: closing all files...
2015-10-28T10:09:21.618+0800 I STORAGE [signalProcessingThread] closeAllFiles() finished
2015-10-28T10:09:21.618+0800 I STORAGE [signalProcessingThread] shutdown: removing fs lock...
2015-10-28T10:09:21.618+0800 I CONTROL [signalProcessingThread] dbexit: rc: 0

###修复启动过程中的两个警告，关于使用root用户启动mongo的警告先忽略
# echo "never" > /sys/kernel/mm/transparent_hugepage/enabled
# echo "never" > /sys/kernel/mm/transparent_hugepage/defrag

###再次重启，后置于后台进程，
# mongod --dbpath /data/mongodata &

###查看启动后的进程
# ps -ef|grep mongo |grep -v grep
root   11115 27956 0 10:11 pts/2  00:00:00 mongod --dbpath /data/mongodata
# lsof -i:27017
COMMAND  PID USER  FD  TYPE  DEVICE SIZE/OFF NODE NAME
mongod 11115 root  5u IPv4 50567119   0t0 TCP *:27017 (LISTEN)

###使用mongo连接到mongod
# mongo
MongoDB shell version: 3.0.6
connecting to: test
2015-10-28T10:14:30.685+0800 I NETWORK [initandlisten] connection accepted from 127.0.0.1:53907 #1 (1 connection now open)
Server has startup warnings: 
2015-10-28T10:11:49.217+0800 I CONTROL [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.
2015-10-28T10:11:49.217+0800 I CONTROL [initandlisten] 
> help
    db.help()          help on db methods
    db.mycoll.help()       help on collection methods
    sh.help()          sharding helpers
    rs.help()          replica set helpers
    help admin          administrative help
    help connect         connecting to a db help
    help keys          key shortcuts
    help misc          misc things to know
    help mr           mapreduce


    show dbs           show database names
    show collections       show collections in current database
    show users          show users in current database
    show profile         show most recent system.profile entries with time >= 1ms
    show logs          show the accessible logger names
    show log [name]       prints out the last segment of log in memory, 'global' is default
    use <db_name>        set current database
    db.foo.find()        list objects in collection foo
    db.foo.find( { a : 1 } )   list objects in foo where a == 1
    it              result of the last line evaluated; use to further iterate
    DBQuery.shellBatchSize = x  set default number of items to display on shell
    exit             quit the mongo shell
> db.getCollection("version");
test.version
> exit
bye

###在安装文件下有README，描述了常用的mongodb相关命令行工具
# more /usr/local/mongodb/README 
MongoDB README
Welcome to MongoDB!
COMPONENTS

 bin/mongod - The database process.
 bin/mongos - Sharding controller.
 bin/mongo - The database shell (uses interactive javascript).

UTILITIES

 bin/mongodump     - MongoDB dump tool - for backups, snapshots, etc..
 bin/mongorestore   - MongoDB restore a dump
 bin/mongoexport    - Export a single collection to test (JSON, CSV)
 bin/mongoimport    - Import from JSON or CSV
 bin/mongofiles    - Utility for putting and getting files from MongoDB GridFS
 bin/mongostat     - Show performance statistics

RUNNING

 For command line options invoke:

  $ ./mongod --help

 To run a single server database:

  $ mkdir /data/db
  $ ./mongod
  $
  $ # The mongo javascript shell connects to localhost and test database by default:
  $ ./mongo 
  > help

DRIVERS

 Client drivers for most programming languages are available at mongodb.org. Use the 
 shell ("mongo") for administrative tasks.

###获取单个命令用法
# <command> --help
# mongod --help|more
Options:

General options:
 -h [ --help ]        show this usage information
 --version          show version information

# mongod --version
db version v3.0.6
git version: 1ef45a23a4c5e3480ac919b28afcba3c615488f2