MongoDB is a free and open-source NoSQL document database.

We will begin with adding MongoDB repositories.

Create a /etc/yum.repos.d/mongodb-org-3.6.repo file so that you can install MongoDB directly, using yum

[mongodb-org-3.6]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/3.6/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-3.6.asc
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You can install latest stable version of MongoDB by typing:

$ sudo yum install -y mongodb-org
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After installation completing, you should start MongoDB service:

$ sudo systemctl start mongod 
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After that you can connect MongoDB shell just typing:

$ mongo
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If you are getting an warning like this :

** WARNING: soft rlimits too low. rlimits set to 4096 processes, 64000 files. 
Number of processes should be at least 32000 : 0.5 times number of files.
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You should edit /etc/security/limits.d/20-nproc.conf file by adding following line to end of the file and you should restart mongod service for applying changes. 

$ mongod soft nproc 32000
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Note: If you want to start mongoDB deamon with system, you should enable it by using systemctl utility :

$ sudo systemctl enable mongod
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