过程如下:

$ brew install mongodb
==> Installing dependencies for mongodb: openssl
==> Installing mongodb dependency: openssl
==> Downloading https://homebrew.bintray.com/bottles/openssl-1.0.2h_1.el_capitan.bottle.tar.gz
######################################################################## 100.0%
==> Pouring openssl-1.0.2h_1.el_capitan.bottle.tar.gz
==> Caveats
A CA file has been bootstrapped using certificates from the system
keychain. To add additional certificates, place .pem files in
/usr/local/etc/openssl/certs

and run
/usr/local/opt/openssl/bin/c_rehash

This formula is keg-only, which means it was not symlinked into /usr/local.

Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries

Generally there are no consequences of this for you. If you build your
own software and it requires this formula, you'll need to add to your
build variables:

LDFLAGS:  -L/usr/local/opt/openssl/lib
CPPFLAGS: -I/usr/local/opt/openssl/include

==> Summary
🍺  /usr/local/Cellar/openssl/1.0.2h_1: 1,691 files, 12M
==> Installing mongodb
==> Downloading https://homebrew.bintray.com/bottles/mongodb-3.2.6.el_capitan.bottle.tar.gz
######################################################################## 100.0%
==> Pouring mongodb-3.2.6.el_capitan.bottle.tar.gz
==> Caveats
To have launchd start mongodb now and restart at login:
brew services start mongodb
Or, if you don't want/need a background service you can just run:
mongod --config /usr/local/etc/mongod.conf
==> Summary
🍺  /usr/local/Cellar/mongodb/3.2.6: 17 files, 263.8M