Manually install (untar) MongoDB 2 and 3 into two different folders, for example
.../mongodb2 .../mongodb3
Create log and data folders for each version
.../mongodb2/log .../mongodb2/data .../mongodb3/log .../mongodb3/data
Create a conf file for each version.
.../mongodb2/data/mongod.conf .../mongodb3/data/mongod.conf
Contents of these files can be something like
logpath=.../mongodb2/log/mongod.log port=27017 dbpath=.../mongodb2/data pidfilepath=.../mongodb2/mongod.pid logpath=.../mongodb3/log/mongod.log port=37017 dbpath=.../mongodb3/data pidfilepath=.../mongodb3/mongod.pid
As you can see here, MongoDB 2 will be running on port 27017 and MongoDB 3 will be running on port 37017
No start each server with the following commands
.../mongodb2/bin/mongod --config .../mongodb2/mongod.conf .../mongodb3/bin/mongod --config .../mongodb3/mongod.conf
That’s it 🙂
Two different command line clients can be run as follows
.../mongodb2/bin/mongo --port 27017 .../mongodb3/bin/mongo --port 37017