Hey there! I’ve run into this exact frustrating issue before—commands working flawlessly in the terminal but failing when run in a script. Let’s break down the most likely causes and how to fix them:

• Use absolute paths for the service command
  Your terminal’s PATH environment variable might include directories that your script’s non-interactive environment doesn’t. First, find where the service command lives by running this in your terminal:

  which service
  

  It’ll probably output something like /usr/sbin/service. Update your script to use this full path instead of just service:

  sudo /usr/sbin/service mongod start
  

• Load your shell’s environment variables in the script
  Interactive terminals load files like ~/.bashrc or ~/.profile that set up your environment, but scripts run in a non-interactive shell and skip these. Add this line at the top of your script (before the mongod command) to load your user’s environment:

  source ~/.bashrc
  

  If you’re running the script with sudo and it’s using root’s environment, try sourcing /root/.bashrc instead.

• Switch to systemctl if your system uses systemd
  Many modern Linux distros use systemd instead of the old SysV init system, and the service command is just a compatibility wrapper. If sudo systemctl start mongod works in your terminal, replace the service command in your script with this one—it’s more reliable in script contexts.

• Fix sudo’s restricted PATH
  Sudo often uses a stripped-down PATH by default, which might exclude the directory where service or mongod’s init scripts live. You can either explicitly set the PATH in your command:

  PATH=/usr/sbin:/usr/bin:/sbin:/bin sudo service mongod start
  

  Or edit the sudoers file (always use visudo to do this safely) to keep your user’s PATH when using sudo. Look for a line starting with Defaults and add:

  Defaults env_keep += "PATH"
  

• Check your script’s shebang line
  Make sure the first line of your script is set to use bash instead of the more minimal sh:

  #!/bin/bash
  

  Some systems link /bin/sh to dash, which has a more limited environment that can cause issues with commands that work in bash.

Give these steps a try—one of them should get your script running the mongod service correctly!

内容的提问来源于stack exchange，提问作者Jon