I\'m on osx6.8 and need to install an earlier version of Mongodb, how do I install an earlier version with HomeBrew? The below didn\'t work :(
dream-2:app2
Instead of using homebrew you can use docker to install as many versions of mongodb as you want. Each mongodb can then run on separate ports.
Install docker with brew cask install docker and then open Docker.app. After docker is running, go to Terminal and install your mongodb version by selecting an image from https://hub.docker.com/_/mongo/ like so: docker run -d -p 28017:27017 --name mongo4 mongo:latest
Verify that it's running with docker ps and you can connect to mongodb from you app using port 28017. Repeat the steps with a different name and port to install more versions. Enjoy!