Mac（OS Catalina）下无法连接MongoDB服务器求助

Hey there, let's work through your MongoDB problems on Catalina one by one—we'll start with the missing tools and then get your server connected smoothly.

Step 1: Reinstall Homebrew (since brew is missing) #

First up, your system doesn't recognize the brew command, which means either Homebrew isn't installed or its path isn't set in your shell's environment variables. Let's fix that:

1. Install Homebrew by running this in your terminal:

   /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
   

   If Catalina blocks the installation due to security settings, head to System Preferences > Security & Privacy and click "Allow" next to the message about the developer tool.

2. Add Homebrew to your shell's PATH (Catalina uses zsh by default, so we'll update ~/.zshrc):

   • Open the config file:

     nano ~/.zshrc
     

   • Add this line at the bottom:

     export PATH="/usr/local/bin:$PATH"
     

   • Save and exit: press Ctrl+O, hit Enter, then Ctrl+X.
   • Reload the config to apply changes:

     source ~/.zshrc
     

   Test if brew works now by running brew --version—you should see its version number pop up.

Step 2: Install MongoDB Community Edition (to fix mongod/mongo not found) #

Since your shell can't find mongod or mongo, we'll install the matching version (4.0.x) using Homebrew to align with your existing shell version:

1. Tap MongoDB's official Homebrew tap:

   brew tap mongodb/brew
   

2. Install the 4.0 community edition (matches your shell version v4.0.16):

   brew install mongodb-community@4.0
   

   This will install both mongod (the server) and mongo (the shell) and add them to your PATH automatically.

Step 3: Start MongoDB Service & Fix Connection Refused Error #

The "Connection refused" error happens because the MongoDB server isn't running. Let's start it and verify everything's working:

1. Start the MongoDB service with Homebrew:

   brew services start mongodb-community@4.0
   

2. Check if the service is running:

   brew services list
   

   You should see mongodb-community@4.0 marked as started.

3. Verify the mongod process is active:

   ps aux | grep mongod
   

   Look for a line starting with mongodb—that means the server is up and running.

4. Test the connection now:

   mongo
   

   You should see the MongoDB shell connect successfully to 127.0.0.1:27017 without the "Connection refused" error.

Extra Troubleshooting If Issues Persist #

• If brew services start fails, try starting mongod manually to see detailed errors:

  mongod --config /usr/local/etc/mongod.conf
  

  Common issues here are missing data directories (check dbPath in the config file—default is /usr/local/var/mongodb) or permission problems. Fix permissions with:

  sudo chown -R $(whoami) /usr/local/var/mongodb
  

• If you still can't find mongo/mongod, double-check your PATH by running echo $PATH—it should include /usr/local/bin.

内容的提问来源于stack exchange，提问作者Daniel Melo