MongoDB won't start

[Alexandru Toth]

Hello

This is my first experience with MongoDB. I am a SQL Server and MySQL DBA, so I am kind of lost here.

The issue is that mongod will not start (3.2 version in centos 7). I have tried every possible thing I can think off, it will just not start. Here are a few useful information:

Log entry:

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] MongoDB starting : pid=2241 port=27017 dbpath=/var/lib/mongo 64-bit host=localhost.localdomain

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] db version v3.2.1

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] git version: a14d55980c2cdc565d4704a7e3ad37e4e535c1b2

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.0.1e-fips 11 Feb 2013

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] allocator: tcmalloc

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] modules: none

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] build environment:

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten]     distmod: rhel70

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten]     distarch: x86_64

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten]     target_arch: x86_64

2016-02-16T20:38:41.954+0100 I CONTROL  [initandlisten] options: { config: "/etc/mongod.conf", net: { bindIp: "0.0.0.0", port: 27017 }, processManagement: { fork: true, pidFilePath: "/var/run/mongodb/mongod.pid" }, storage: { dbPath: "/var/lib/mongo", journal: { enabled: true } }, systemLog: { destination: "file", logAppend: true, path: "/var/log/mongodb/mongod.log" } }

2016-02-16T20:38:41.997+0100 I -        [initandlisten] Detected data files in /var/lib/mongo created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.

2016-02-16T20:38:41.997+0100 I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=1G,session_max=20000,eviction=(threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000),checkpoint=(wait=60,log_size=2GB),statistics_log=(wait=0),

2016-02-16T20:38:42.150+0100 E STORAGE  [initandlisten] WiredTiger (13) [1455651522:150880][2241:0x7fa44d9c4dc0], txn-recover: /var/lib/mongo/journal/WiredTigerLog.0000000008: Permission denied

2016-02-16T20:38:42.150+0100 E STORAGE  [initandlisten] WiredTiger (13) [1455651522:150955][2241:0x7fa44d9c4dc0], txn-recover: Recovery failed: Permission denied

2016-02-16T20:38:42.152+0100 I -        [initandlisten] Assertion: 28595:13: Permission denied

2016-02-16T20:38:42.177+0100 I STORAGE  [initandlisten] exception in initAndListen: 28595 13: Permission denied, terminating

2016-02-16T20:38:42.177+0100 I CONTROL  [initandlisten] dbexit:  rc: 100

Permissions:

-rwxr-xr-x 1 mongod mongod 16384 Feb 16 20:44 collection-0-1312287423206501205.wt

-rwxr-xr-x 1 mongod mongod 36864 Feb 16 20:44 collection-0--3025592519689880938.wt

-rwxr-xr-x 1 mongod mongod 16384 Feb 16 20:44 collection-2-1312287423206501205.wt

drwxr-xr-x 2 mongod mongod  4096 Feb 16 20:44 diagnostic.data

-rwxr-xr-x 1 mongod mongod 16384 Feb 16 20:44 index-1-1312287423206501205.wt

-rwxr-xr-x 1 mongod mongod 36864 Feb 16 20:44 index-1--3025592519689880938.wt

-rwxr-xr-x 1 mongod mongod 16384 Feb 16 18:00 index-3-1312287423206501205.wt

-rwxr-xr-x 1 mongod mongod 16384 Feb 16 18:00 index-4-1312287423206501205.wt

drwxr-xr-x 2 mongod mongod   107 Feb 16 20:44 journal

-rwxr-xr-x 1 mongod mongod 32768 Feb 16 20:44 _mdb_catalog.wt

-rwxr-xr-x 1 mongod mongod     0 Feb 16 20:44 mongod.lock

-rwxr-xr-x 1 mongod mongod 36864 Feb 16 20:44 sizeStorer.wt

-rwxr-xr-x 1 mongod mongod    95 Feb 16 17:54 storage.bson

-rwxr-xr-x 1 mongod mongod    49 Feb 16 17:54 WiredTiger

-rwxr-xr-x 1 mongod mongod  4096 Feb 16 20:44 WiredTigerLAS.wt

-rwxr-xr-x 1 mongod mongod    21 Feb 16 17:54 WiredTiger.lock

-rwxr-xr-x 1 mongod mongod   925 Feb 16 20:44 WiredTiger.turtle

-rwxr-xr-x 1 mongod mongod 53248 Feb 16 20:44 WiredTiger.wt

Configuration file:

# mongod.conf

# for documentation of all options, see:

#   http://docs.mongodb.org/manual/reference/configuration-options/

# where to write logging data.

systemLog:

  destination: file

  logAppend: true

  path: /var/log/mongodb/mongod.log

# Where and how to store data.

storage:

  dbPath: /var/lib/mongo/

  journal:

    enabled: true

#  engine:

#  mmapv1:

#  wiredTiger:

# how the process runs

processManagement:

  fork: true  # fork and run in background

  pidFilePath: /var/run/mongodb/mongod.pid  # location of pidfile

# network interfaces

net:

  port: 27017

  bindIp: 0.0.0.0  # Listen to local interface only, comment to listen on all interfaces.

security:

        authorization : enabled

Conf file is default, exception is the security feature which is enabled. It fails with permission error. I have even tried to set permissions on /var/lib/mongo to 777. Still the same error. 

I could really use some help on this one.

Thank you in advance!

[Wan Bachtiar]

Hi Alexandru,

To better help understand your setup :

• Which user does the mongod process running as ?
• How did you run mongod ? through startup /etc/init.d/mongod ?
• Can you post the output of ls -laR /var/lib/mongodb ?
• Is this the first installation of MongoDB on the machine or was it an upgrade ?

I have even tried to set permissions on /var/lib/mongo to 777

Note that you need the option -R for chmod to be recursive. As the file with permission issue is in /var/lib/mongo/journal/, depending on how you set the permission to 777 you may not have changed the file’s permission.

You may also find these useful:

• Data directories and permissions
• Configure SELinux

Regards,

Wan.

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