Unable to git clone , Failed to connect to github.com port 443: Network is unreachable

Recently, I have encountered following problem. Might be useful for others who face same error.

I have two different Internet service provider. With one ISP, it works fine but with others it fails.

For example:

git clone https://github.com/odoo/odoo.git

It throws me following error:

fatal: unable to access 'https://github.com/odoo/odoo.git': Failed to connect to github.com port 443: Network is unreachable

I have solved with following trick.

ping github.com
PING github.com (192.30.253.112) 56(84) bytes of data.

Add  192.30.253.112 github.com in /etc/hosts file.