If you are setting up RoR on a system, and while installing RVM you get an error like

curl: (7) Failed to connect to get.rvm.io port 443: Network is unreachable

this is due to mis-configured ipv4 & ipv6.

As you already know that RVM is a version manager and it will help us to install & manage different versions of Ruby on the same system and easily switch between them.

So if you are installing it using curl you need to download its signature and import it.

I assume you have already downloaded the signature & u have imported it by running

      curl -#LO https://rvm.io/mpapis.asc
      gpg --import mpapis.asc

and now if u are installing it using

\curl -sSL https://get.rvm.io | bash 

and you get an error like

curl: (7) Failed to connect to get.rvm.io port 443: Network is unreachable

Then the problem is with the mis-cinfigured ipv6.

To overcome this problem, run the following command

echo ipv4 >> ~/.curlrc

The above command will remember the --ip4 flag for all curl commands and then it will force curl to use ipv4 instead of ipv6, because curl causes issue with ipv6 configuration in most of the systems.

After executing this command the above issue is resolved, & now we can successfully install RVM using

\curl -sSL https://get.rvm.io | bash