In this tutorial we will learn,how to install MongoDB server on Ubuntu 12.04 LTS.
MongoDB is one the popular nosql database.It is a cross-platform document-oriented database system.MongoDB has its interactive shell called mongo .In recent years,many companies started using MongoDB.To know about more details on MongoDB,you can visit the Wikipedia link

How to install MongoDB server on Ubuntu 12.04 LTS

To install MongoDB server on Ubuntu 12.04 LTS,follow the given below steps.

Step 1: Log into your Ubuntu system and run below given command

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10
sudo echo 'deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen' | sudo tee /etc/apt/sources.list.d/mongodb.list

Step 2: Now update the apt source

sudo apt-get update

Step 3: Install MongoDB with apt-get command.It will install the latest
stable MongoDB in the system.

sudo apt-get install mongodb-10gen

Step 4: After installing the mongodb in Ubuntu.It will be automatically started.
You can check the running status by using the below given command

sudo service mongodb status

Alternatively, you can also use the ps command.It will show the running process

ps -ef|grep mongo

Given below is the example from my system

root@ubuntu:~# ps -ef|grep mongodb
mongodb 2841 1 7 14:05 ? 00:00:08 /usr/bin/mongod –config /etc/mongodb.conf
root 2861 2392 0 14:07 pts/0 00:00:00 grep –color=auto mongodb
root@ubuntu:~#

To stop the MongoDB run below given command

service mongodb stop

To start the MongoDB run below given command

service mongodb start

To restart the MongoDB run below given command

service mongodb restart

Step 5: You can check the listening port of running MongoDB by using netstat command.

NOTE: MongoDB using the port no. 27017 and 28017
(MongoDB default port number)

netstat -tanp |grep mongo

Below given is reference from my system

root@ubuntu:~# netstat -tanp|grep mongo
tcp 0 0 0.0.0.0:27017 0.0.0.0:* LISTEN 2841/mongod
tcp 0 0 0.0.0.0:28017 0.0.0.0:* LISTEN 2841/mongod
root@ubuntu:~#

Step 6 : To acces the MongoDB console,you have to run only mongo command

When first time you run mongo command,you will get welcome message as well as MongoDB version information

See the below given reference

root@ubuntu:~# mongo
MongoDB shell version: 2.4.9
connecting to: test
Welcome to the MongoDB shell.
For interactive help, type "help".
For more comprehensive documentation, see
	http://docs.mongodb.org/
Questions? Try the support group
	http://groups.google.com/group/mongodb-user
> 

Now you will be at mongo console

To exit from mongo console

To exit from mongo console.In console type the command exit and hit enter.
You can also press CTRL + D key from your keyboard for exit .You will bye message on exit.

See below given example for exit from mongo console.Because now I am again entering into mongo console,the welcome message will not be there.

Other important information of MongoDB

(1) MongoDB configuration path is /etc/mongodb.conf.

root@ubuntu:~# cat /etc/mongodb.conf |egrep -v '^#|^$'
dbpath=/var/lib/mongodb
logpath=/var/log/mongodb/mongodb.log
logappend=true
root@ubuntu:~#

Note: I used the command egrep -v '^#|^$', to do not show commented lines(#) and blank lines from the file /etc/mongodb.conf. the file has lots of commented options.

(2) MongoDB data directory bydefault path is /var/lib/mongodb
Below given is the reference from my system.

root@ubuntu:~# ls -l /var/lib/mongodb/
total 81932
drwxr-xr-x 2 mongodb nogroup     4096 Feb 16 18:40 journal
-rw------- 1 mongodb nogroup 67108864 Feb 16 18:40 local.0
-rw------- 1 mongodb nogroup 16777216 Feb 16 18:40 local.ns
-rwxr-xr-x 1 mongodb nogroup        5 Feb 16 18:40 mongod.lock
root@ubuntu:~# 

(3) MongoDB log file path is /var/log/mongodb/mongodb.log