Virtual Machines

affirmation60

Hi Guys,
Not being in the slightest bit techi would someone be able to explain to me the fors and against of a Virtual Machine and i it correct that someone told me you can run 2 screens side by side and each screen is basically run as separate machines, does it also change your IP address, sorry if all this sounds dumb but i really dont have a clue about this kind of stuff :doh:

debitcardmayhem

Why? is the best question, i.e. what are you trying to achieve

InsideInsurance

affirmation60 wrote: »

basically run as separate machines, does it also change your IP address

Basically yes, if you delve deeper then "it depends"

"IP address" is not as universal as you may think. If you have a network of 10,000 computers each one on the network will have a unique IP however if there is only a single access point to the internet the outside world will only see a single IP for all 10,000 machines. With a few ISPs, even all their customers will have a single IP so the ISP only sees 1 IP for the network and the outside world sees only 1 IP for all customers of that ISP

securityguy

InsideInsurance wrote: »

Basically yes, if you delve deeper then "it depends"

"IP address" is not as universal as you may think. If you have a network of 10,000 computers each one on the network will have a unique IP

In fact, the standard set-up for desktop virtualisation has each of the guest operating systems NAT'd behind the host operating system's IP number. There are other ways to do it, and it's perfectly possible to instead bridge them and have them each get an IP number on the LAN. But out of the box, the default configuration has one IP number per hardware platform.

I've got a /28 (16 IPv4 addresses) and a /48 (1208925819614629174706176 IPv6 addresses) at home, so all the VMs have their own public IP number. But that's not the standard setup.

jbainbridge

securityguy wrote: »

In fact, the standard set-up for desktop virtualisation has each of the guest operating systems NAT'd behind the host operating system's IP number. There are other ways to do it, and it's perfectly possible to instead bridge them and have them each get an IP number on the LAN. But out of the box, the default configuration has one IP number per hardware platform.

I've got a /28 (16 IPv4 addresses) and a /48 (1208925819614629174706176 IPv6 addresses) at home, so all the VMs have their own public IP number. But that's not the standard setup.

You don't say!

esuhl

affirmation60 wrote: »

Hi Guys,
Not being in the slightest bit techi would someone be able to explain to me the fors and against of a Virtual Machine and i it correct that someone told me you can run 2 screens side by side and each screen is basically run as separate machines, does it also change your IP address, sorry if all this sounds dumb but i really dont have a clue about this kind of stuff :doh:

Imagine a window on your PC in which you can see the whole screen of another computer. That computer can be running any operating system (so long as it's supported/compatible with the virtualisation software).

A virtual machine won't change your existing IP addresses (assuming you're using IPv4). If you use network address translation (NAT) to connect the virtual machine's network interface to your network, the guest operating system (i.e. the one running as a virtual machine) will have its own local IP address on your local network's subnet. The IP address of your internet connection will be used to route all internet traffic from all your devices.

https://en.wikipedia.org/wiki/Network_address_translation

Mr_Toad

As others have said. What are you wanting to do?

I have several VMs on my Mac;

Oracle Enterprise Linux for Oracle development stuff.
Windows 8 - solely so I know what I'm doing when friends ask for support.
Raspberry Pi, again for development work and testing scripts that I wrote for my robot.
Several different Linux distros for testing of scripts etc.

securityguy

esuhl wrote: »

If you use network address translation (NAT) to connect the virtual machine's network interface to your network, the guest operating system (i.e. the one running as a virtual machine) will have its own local IP address on your local network's subnet.

That's not quite right. If you run NAT on the host, which is the standard set up, then the guests have separate IP numbers on a network which is internal to the host machine. They're all NAT'd to the address of the host as they are routed on to your local network, and then NAT'd again when they leave your local network for the Internet (assuming you're NAT'd at that point).

If you want each guest VM to have a separate IP number on the local network, so that you can (for example) ssh/rdp/vnc in to the guest from elsewhere on the local network, then you need the host to bridge, not NAT.

paddyrg

If you're asking, then VM's probably aren't the answer you're looking for.

tronator

securityguy wrote: »

In fact, the standard set-up for desktop virtualisation has each of the guest operating systems NAT'd behind the host operating system's IP number. There are other ways to do it, and it's perfectly possible to instead bridge them and have them each get an IP number on the LAN. But out of the box, the default configuration has one IP number per hardware platform.

I've got a /28 (16 IPv4 addresses) and a /48 (1208925819614629174706176 IPv6 addresses) at home, so all the VMs have their own public IP number. But that's not the standard setup.

I think the OP's head just exploded

@OP: If you only want to use 2 screens, then you only need a graphics card with two outputs and configure it accordingly.

onomatopoeia99

securityguy wrote: »

I've got a /28 (16 IPv4 addresses) and a /48 (1208925819614629174706176 IPv6 addresses) at home, so all the VMs have their own public IP number. But that's not the standard setup.

Mine is similar, although no IPv6 yet (soon though and driven by virtualisation).