Symptom: You already have vagrant installed. However, when you type “vagrant ssh”, the terminal hangs for a minute or so before failing out with a timeout error message. You may also see a GUI error “VT-x/AMD-V hardware acceleration is not available…”.
(Likely) cause: Hardware acceleration is not enabled on your computer. On 64-bit host OSs (i.e. most computers these days), acceleration must be enabled in the BIOS to run 64-bit guests in VirtualBox and Vagrant.
Solution: Ensure that HW virtualization acceleration is enabled in the BIOS.