On my CentOS 7.2 laptop, I had used VirtualBox to create a Ubuntu 14.0.4 VM. Quite a while ago, I went through the steps required so that I could reach a port on the VM from the host. This required adding a "host-only adapter" network entry to the VM settings. This was working fine.
Some time has passed.
Since then, I had installed Android Studio on the laptop, which ended up enabling KVM so that I could run the emulator. After that, I realized trying to use both KVM and VirtualBox couldn't work. I figured out how to disable KVM so that I could use my VirtualBox VM again. That was a couple of weeks ago.
Today I tried to connect to the port on the VM, which was working before. Now, it's timing out. The "host-only adapter" is still set on the VM.
I also tried pinging the IP, and that times out.
What info can I provide so that someone could diagnose this?