1) "Cloud" is not what you'll be installing on. Vicidial is not a service with a cloud install mechanism. You'll be installing on a server in a colocation facility. The server may be "virtual" or "dedicated", but it's not a cloud application, just NOT in your facility.
2) Do NOT install Vicidial in a virtual server unless you've got money to toss into the abyss. It will work for one or two agents, but not a call center. Hardware Only when installing in a colocation facility or anywhere else. For testing with one or two agents, virtual will work fine, but when you scale up and log all your agents into the system, it will never be stable if sharing CPUs. You've been warned.
3) Many colocation facilities willl allow booting from a custom .iso for installation. Complex, tricky, may involve several calls to tech support and MAY even require bypassing tech support with the colo to get support from the manufacturer of the KVM or Servers remote access tools to make it work. But it doesn't always work in the end.
4) We (and I'm sure The Vicidial Group) have Fiber-based internet and have clients all over the world with call centers all over as well. Be sure you are choosing a solution that will suit your needs. Vicidial support isn't necessary for the hardware or OS, but it can sure come in handy when you have a problem. By comparison to what may happen if you have no support available on a busy day when your server mysteriously stops working (Welcome to Linux!), the cost at a generic "cloud" facility with no humans (or no humans who know linux, or no humans who know PBX, or no humans who know Linux ... much less humans who know ALL of these) could get very expensive due to lost production very quickly.
5) Vicidial scratch install can be done through Ubuntu and CentOS. If Goutodial's installation instructions (in their wiki) are available, they are very useful. Unfortunately, the last time I checked they were broken and in the middle of an upgrade. Goautodial has modified web pages, some of which are broken, all of which are at least one full version behind ... BUT: it is a solid install and also (historically) installs all the stock Vicidial pages and those work without fail. Goautodial can also be upgraded to the latest vicidial install, which breaks much of the goautodial modified pages, but still results in an up-to-date fully-functional Vicidial installation on CentOS.