Is there anyway we can setup SharePoint framework development environment offline without internet connection?
Following this instruction,
https://docs.microsoft.com/en-us/sharepoint/dev/spfx/set-up-your-development-environment
It failed on the second step, npm install -g yo gulp
If your node modules were already installed, then yes, you can develop offline. But the npm install command very specifically downloads and installs the package you specify.
If you can find a colleague who already has those modules installed and you can copy from their machine to yours, you could potentially get it setup without an internet connection, but you are going to have to get those SPFx packages (Yeoman Gulp and Microsoft Generator) from somewhere.
