MongoDB警告信息：
1. WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine 
2. WARNING: Access control is not enabled for the database. 
3. WARNING: /sys/kernel/mm/transparent_hugepage/enabled is ‘always’. 
4. WARNING: /sys/kernel/mm/transparent_hugepage/defrag is ‘always’.

1.WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine（强烈建议使用带WiredTiger存储引擎的XFS文件系统）

报这个错是因为我的虚拟环境使用的是EXT4文件系统，官方不建议，但不影响使用

在Linux上运行MongoDB时，官方建议使用Linux内核版本2.6.36或更高版本，使用XFS或EXT4文件系统。 如果可能，最好使用XFS，因为它通常与MongoDB表现更好。

使用WiredTiger存储引擎，强烈建议使用XFS，以避免在使用EXT4与WiredTiger时可能发生的性能问题。

使用MMAPv1存储引擎，MongoDB在使用它们之前预先分配其数据库文件，并经常创建大文件。 因此，官方建议使用XFS或EXT4文件系统。 如果可能，请使用XFS，因为它通常与MongoDB表现更好。

2.WARNING: Access control is not enabled for the database.（数据库未启用访问控制）

报这个错是因为MongoDB需要有一个安全库来开启数据库访问控制

在MongoDB部署上启用访问控制会强制执行身份验证，要求用户识别自己。当访问启用了访问控制的MongoDB部署时，用户只能执行由其角色确定的操作。

  • 不使用访问控制模式开启mongdb
root@localhost ~]# mongod --dbpath /var/lib/mongo

--27T03::14.853+ I CONTROL  [initandlisten] MongoDB starting : pid= port= dbpath=/var/lib/mongo -bit host=localhost.localdomain

--27T03::14.853+ I CONTROL  [initandlisten] db version v3.4.9

--27T03::14.853+ I CONTROL  [initandlisten] git version: 876ebee8c7dd0e2d992f36a848ff4dc50ee6603e

--27T03::14.853+ I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.0.1e-fips  Feb

--27T03::14.853+ I CONTROL  [initandlisten] allocator: tcmalloc

--27T03::14.853+ I CONTROL  [initandlisten] modules: none

--27T03::14.853+ I CONTROL  [initandlisten] build environment:

--27T03::14.853+ I CONTROL  [initandlisten]     distmod: rhel70

--27T03::14.853+ I CONTROL  [initandlisten]     distarch: x86_64

--27T03::14.853+ I CONTROL  [initandlisten]     target_arch: x86_64

--27T03::14.853+ I CONTROL  [initandlisten] options: { storage: { dbPath: "/var/lib/mongo" } }

--27T03::14.971+ I -        [initandlisten] Detected data files in /var/lib/mongo created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.

--27T03::14.971+ I STORAGE  [initandlisten]

--27T03::14.971+ I STORAGE  [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine

--27T03::14.971+ I STORAGE  [initandlisten] **          See http://dochub.mongodb.org/core/prodnotes-filesystem

--27T03::14.971+ I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=1455M,session_max=,eviction=(threads_min=,threads_max=),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=),checkpoint=(wait=,log_size=2GB),statistics_log=(wait=),

--27T03::16.364+ I CONTROL  [initandlisten]

--27T03::16.364+ I CONTROL  [initandlisten] ** WARNING: Access control is not enabled for the database.

--27T03::16.364+ I CONTROL  [initandlisten] **          Read and write access to data and configuration is unrestricted.

--27T03::16.364+ I CONTROL  [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.

--27T03::16.364+ I CONTROL  [initandlisten]

--27T03::16.365+ I CONTROL  [initandlisten]

--27T03::16.365+ I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/enabled is 'always'.

--27T03::16.365+ I CONTROL  [initandlisten] **        We suggest setting it to 'never'

--27T03::16.365+ I CONTROL  [initandlisten]

--27T03::16.365+ I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/defrag is 'always'.

--27T03::16.365+ I CONTROL  [initandlisten] **        We suggest setting it to 'never'

--27T03::16.365+ I CONTROL  [initandlisten]

--27T03::16.634+ I FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/var/lib/mongo/diagnostic.data'

--27T03::16.635+ I NETWORK  [thread1] waiting for connections on port

--27T03::33.704+ I NETWORK  [thread1] connection accepted from 127.0.0.1: # ( connection now open)

--27T03::33.705+ I NETWORK  [conn1] received client metadata from 127.0.0.1: conn1: { application: { name: "MongoDB Shell" }, driver: { name: "MongoDB Internal Client", version: "3.4.9" }, os: { type: "Linux", name: "CentOS Linux release 7.3.1611 (Core) ", architecture: "x86_64", version: "Kernel 3.10.0-514.26.2.el7.x86_64" } }

--27T03::15.311+ I COMMAND  [conn1] command admin.system.users appName: "MongoDB Shell" command: insert { insert: "system.users", documents: [ { _id: "admin.myUserAdmin", user: "myUserAdmin", db: "admin", credentials: { SCRAM-SHA-: { iterationCount: , salt: "pUdmLObMsG3wKU7MZDFU1g==", storedKey: "wlCaAzPOS+u7CUqzMKxeZB+DFkE=", serverKey: "KwP12FF1ASziFPVstN8mLrPLg+A=" } }, roles: [ { role: "userAdminAnyDatabase", db: "admin" } ] } ] } ninserted: keysInserted: numYields: reslen: locks:{ Global: { acquireCount: { r: , w:  } }, Database: { acquireCount: { W:  } }, Collection: { acquireCount: { w:  } } } protocol:op_query 145ms

--27T03::15.311+ I COMMAND  [conn1] command admin.$cmd appName: "MongoDB Shell" command: createUser { createUser: "myUserAdmin", pwd: "xxx", roles: [ { role: "userAdminAnyDatabase", db: "admin" } ], digestPassword: false, writeConcern: { w: "majority", wtimeout: 600000.0 } } numYields: reslen: locks:{ Global: { acquireCount: { r: , w:  } }, Database: { acquireCount: { W:  } }, Collection: { acquireCount: { w:  } } } protocol:op_command 202ms
  • 连接到instance
[root@localhost ~]# mongo

MongoDB shell version v3.4.9

connecting to: mongodb://127.0.0.1:27017

MongoDB server version: 3.4.

Server has startup warnings:

--27T03::14.971+ I STORAGE  [initandlisten]

--27T03::14.971+ I STORAGE  [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine

--27T03::14.971+ I STORAGE  [initandlisten] **          See http://dochub.mongodb.org/core/prodnotes-filesystem

--27T03::16.364+ I CONTROL  [initandlisten]

--27T03::16.364+ I CONTROL  [initandlisten] ** WARNING: Access control is not enabled for the database.

--27T03::16.364+ I CONTROL  [initandlisten] **          Read and write access to data and configuration is unrestricted.

--27T03::16.364+ I CONTROL  [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.

--27T03::16.364+ I CONTROL  [initandlisten]

--27T03::16.365+ I CONTROL  [initandlisten]

--27T03::16.365+ I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/enabled is 'always'.

--27T03::16.365+ I CONTROL  [initandlisten] **        We suggest setting it to 'never'

--27T03::16.365+ I CONTROL  [initandlisten]

--27T03::16.365+ I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/defrag is 'always'.

--27T03::16.365+ I CONTROL  [initandlisten] **        We suggest setting it to 'never'

--27T03::16.365+ I CONTROL  [initandlisten]

>
  • 在admin数据库中创建administrator 用户
> use admin

switched to db admin

> db.createUser(

...   {

...     user: "myUserAdmin",

...     pwd: "abc123",

...     roles: [ { role: "userAdminAnyDatabase", db: "admin" } ]

...   }

... )

Successfully added user: {

    "user" : "myUserAdmin",

    "roles" : [

        {

            "role" : "userAdminAnyDatabase",

            "db" : "admin"

        }

    ]

}

> exit

bye
  • 重启Mongodb
使用Ctrl+c退出原mongod

q^H

^C2017--27T03::25.685+ I CONTROL  [signalProcessingThread] got signal  (Interrupt), will terminate after current cmd ends

--27T03::25.685+ I NETWORK  [signalProcessingThread] shutdown: going to close listening sockets...

--27T03::25.685+ I NETWORK  [signalProcessingThread] closing listening socket:

--27T03::25.685+ I NETWORK  [signalProcessingThread] closing listening socket:

--27T03::25.685+ I NETWORK  [signalProcessingThread] removing socket file: /tmp/mongodb-.sock

--27T03::25.685+ I NETWORK  [signalProcessingThread] shutdown: going to flush diaglog...

--27T03::25.685+ I FTDC     [signalProcessingThread] Shutting down full-time diagnostic data capture

--27T03::25.687+ I STORAGE  [signalProcessingThread] WiredTigerKVEngine shutting down

--27T03::25.770+ I STORAGE  [signalProcessingThread] shutdown: removing fs lock...

--27T03::25.770+ I CONTROL  [signalProcessingThread] now exiting

--27T03::25.770+ I CONTROL  [signalProcessingThread] shutting down with code:
  • 开启访问控制启动Mongod
[root@localhost ~]# mongod --auth --dbpath /var/lib/mongo

--27T03::40.034+ I CONTROL  [initandlisten] MongoDB starting : pid= port= dbpath=/var/lib/mongo -bit host=localhost.localdomain

--27T03::40.034+ I CONTROL  [initandlisten] db version v3.4.9

--27T03::40.034+ I CONTROL  [initandlisten] git version: 876ebee8c7dd0e2d992f36a848ff4dc50ee6603e

--27T03::40.034+ I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.0.1e-fips  Feb

--27T03::40.034+ I CONTROL  [initandlisten] allocator: tcmalloc

--27T03::40.034+ I CONTROL  [initandlisten] modules: none

--27T03::40.034+ I CONTROL  [initandlisten] build environment:

--27T03::40.034+ I CONTROL  [initandlisten]     distmod: rhel70

--27T03::40.034+ I CONTROL  [initandlisten]     distarch: x86_64

--27T03::40.034+ I CONTROL  [initandlisten]     target_arch: x86_64

--27T03::40.034+ I CONTROL  [initandlisten] options: { security: { authorization: "enabled" }, storage: { dbPath: "/var/lib/mongo" } }

--27T03::40.054+ I -        [initandlisten] Detected data files in /var/lib/mongo created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.

--27T03::40.054+ I STORAGE  [initandlisten]

--27T03::40.054+ I STORAGE  [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine

--27T03::40.054+ I STORAGE  [initandlisten] **          See http://dochub.mongodb.org/core/prodnotes-filesystem

--27T03::40.054+ I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=1455M,session_max=,eviction=(threads_min=,threads_max=),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=),checkpoint=(wait=,log_size=2GB),statistics_log=(wait=),

--27T03::40.420+ I CONTROL  [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.

--27T03::40.420+ I CONTROL  [initandlisten]

--27T03::40.420+ I CONTROL  [initandlisten]

--27T03::40.420+ I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/enabled is 'always'.

--27T03::40.420+ I CONTROL  [initandlisten] **        We suggest setting it to 'never'

--27T03::40.420+ I CONTROL  [initandlisten]

--27T03::40.420+ I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/defrag is 'always'.

--27T03::40.420+ I CONTROL  [initandlisten] **        We suggest setting it to 'never'

--27T03::40.420+ I CONTROL  [initandlisten]

--27T03::40.422+ I FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/var/lib/mongo/diagnostic.data'

--27T03::40.422+ I NETWORK  [thread1] waiting for connections on port

--27T03::07.458+ I NETWORK  [thread1] connection accepted from 127.0.0.1: # ( connection now open)

--27T03::07.458+ I NETWORK  [conn1] received client metadata from 127.0.0.1: conn1: { application: { name: "MongoDB Shell" }, driver: { name: "MongoDB Internal Client", version: "3.4.9" }, os: { type: "Linux", name: "CentOS Linux release 7.3.1611 (Core) ", architecture: "x86_64", version: "Kernel 3.10.0-514.26.2.el7.x86_64" } }

--27T03::07.477+ I ACCESS   [conn1] Successfully authenticated as principal myUserAdmin on admin

--27T03::07.478+ I ACCESS   [conn1] Unauthorized: not authorized on admin to execute command { getLog: "startupWarnings" }

--27T03::07.665+ I ACCESS   [conn1] Unauthorized: not authorized on admin to execute command { replSetGetStatus: 1.0, forShell: 1.0 }

--27T03::26.104+ I -        [conn1] end connection 127.0.0.1: ( connection now open)

--27T03::29.697+ I NETWORK  [thread1] connection accepted from 127.0.0.1: # ( connection now open)

--27T03::29.697+ I NETWORK  [conn2] received client metadata from 127.0.0.1: conn2: { application: { name: "MongoDB Shell" }, driver: { name: "MongoDB Internal Client", version: "3.4.9" }, os: { type: "Linux", name: "CentOS Linux release 7.3.1611 (Core) ", architecture: "x86_64", version: "Kernel 3.10.0-514.26.2.el7.x86_64" } }

--27T03::29.713+ I ACCESS   [conn2] Successfully authenticated as principal myTester on test

--27T03::29.714+ I ACCESS   [conn2] Unauthorized: not authorized on admin to execute command { getLog: "startupWarnings" }

--27T03::29.715+ I ACCESS   [conn2] Unauthorized: not authorized on admin to execute command { replSetGetStatus: 1.0, forShell: 1.0 }
  • 刚刚新建的用户myUserAdmin连接数据
[root@localhost ~]# mongo --port  -u "myUserAdmin" -p "abc123" --authenticationDatabase "admin"

MongoDB shell version v3.4.9

connecting to: mongodb://127.0.0.1:27017/

MongoDB server version: 3.4.

>
创建新数据库test并在其中创建用户myTester

> use test

switched to db test

> db.createUser(

...   {

...     user: "myTester",

...     pwd: "xyz123",

...     roles: [ { role: "readWrite", db: "test" },

...              { role: "read", db: "reporting" } ]

...   }

... )

Successfully added user: {

    "user" : "myTester",

    "roles" : [

        {

            "role" : "readWrite",

            "db" : "test"

        },

        {

            "role" : "read",

            "db" : "reporting"

        }

    ]

}

> exit

bye
  • 使用新建的myTester用户连接数据库
[root@localhost ~]# mongo --port  -u "myTester" -p "xyz123" --authenticationDatabase "test"

MongoDB shell version v3.4.9

connecting to: mongodb://127.0.0.1:27017/

MongoDB server version: 3.4.

3.WARNING: /sys/kernel/mm/transparent_hugepage/enabled is ‘always’.与4.WARNING: /sys/kernel/mm/transparent_hugepage/defrag is ‘always’.

这两个问题是CentOS7特有的，因为从CentOS7版本开始会默认启用Transparent Huge Pages(THP) 
Transparent Huge Pages(THP)本意是用来提升内存性能，但某些数据库厂商还是建议直接关闭THP(比如说Oracle、MariaDB、MongoDB等)，否则可能会导致性能出现下降。

  • 查看THP状态
[root@localhost ~]#  cat /sys/kernel/mm/transparent_hugepage/defrag

[always] madvise never

[root@localhost ~]# cat /sys/kernel/mm/transparent_hugepage/enabled

[always] madvise never
  • 修改系统配置
[root@localhost ~]# vim /etc/rc.d/rc.local

#!/bin/bash

# THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES

#

# It is highly advisable to create own systemd services or udev rules

# to run scripts during boot instead of using this file.

#

# In contrast to previous versions due to parallel execution during boot

# this script will NOT be run after all other services.

#

# Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure

# that this script will be executed during boot.

touch /var/lock/subsys/local

if test -f /sys/kernel/mm/transparent_hugepage/enabled; then

 echo never > /sys/kernel/mm/transparent_hugepage/enabled

 fi

 if test -f /sys/kernel/mm/transparent_hugepage/defrag; then

 echo never > /sys/kernel/mm/transparent_hugepage/defrag

 fi

[root@localhost ~]# chmod +x /etc/rc.d/rc.local
  • 重启虚拟机
[root@localhost ~]# shutdown -r
  • 再次查看THP状态
[root@localhost ~]#  cat /sys/kernel/mm/transparent_hugepage/defrag

always madvise [never]

[root@localhost ~]# cat /sys/kernel/mm/transparent_hugepage/enabled

always madvise [never]

已经改为了禁用THP

  • 启动mongod
[root@localhost ~]# mongod --auth --dbpath /var/lib/mongo

--27T03::50.174+ I CONTROL  [initandlisten] MongoDB starting : pid= port= dbpath=/var/lib/mongo -bit host=localhost.localdomain

--27T03::50.175+ I CONTROL  [initandlisten] db version v3.4.9

--27T03::50.175+ I CONTROL  [initandlisten] git version: 876ebee8c7dd0e2d992f36a848ff4dc50ee6603e

--27T03::50.175+ I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.0.1e-fips  Feb

--27T03::50.175+ I CONTROL  [initandlisten] allocator: tcmalloc

--27T03::50.175+ I CONTROL  [initandlisten] modules: none

--27T03::50.175+ I CONTROL  [initandlisten] build environment:

--27T03::50.175+ I CONTROL  [initandlisten]     distmod: rhel70

--27T03::50.175+ I CONTROL  [initandlisten]     distarch: x86_64

--27T03::50.175+ I CONTROL  [initandlisten]     target_arch: x86_64

--27T03::50.175+ I CONTROL  [initandlisten] options: { security: { authorization: "enabled" }, storage: { dbPath: "/var/lib/mongo" } }

--27T03::50.195+ I -        [initandlisten] Detected data files in /var/lib/mongo created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.

--27T03::50.195+ I STORAGE  [initandlisten]

--27T03::50.195+ I STORAGE  [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine

--27T03::50.195+ I STORAGE  [initandlisten] **          See http://dochub.mongodb.org/core/prodnotes-filesystem

--27T03::50.195+ I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=1455M,session_max=,eviction=(threads_min=,threads_max=),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=),checkpoint=(wait=,log_size=2GB),statistics_log=(wait=),

--27T03::50.689+ I CONTROL  [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.

--27T03::50.689+ I CONTROL  [initandlisten]

--27T03::50.692+ I FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/var/lib/mongo/diagnostic.data'

--27T03::50.693+ I NETWORK  [thread1] waiting for connections on port
  • 进入数据库
[root@localhost ~]# mongo

MongoDB shell version v3.4.9

connecting to: mongodb://127.0.0.1:27017

MongoDB server version: 3.4.

>

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