3.4 Virtual Machine, Network, Hard Disk Creation Part 4
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5 hours 8 minutes
Okay, So conceptualizing an external network. So part of what makes understanding the external virtual switch artificially difficult
is the way that the related settings are worded. For whatever reason, they decided to choose it this way and make it make it this way in terms of
how they word it. It can be a little confusing if you if you're not sure. S O. J s has just said, actually, hopefully you can explain when we would create a private and internal network instead of external. Yeah. I mean, I'm happy to answer that now. Actually, Jaish
it's effectively down to you as the person running the network. So
it's It's all about security. External means that your you can take that hyper V host on guest operating systems and attach them to other networks. So if you wanted, for example, to have a hyper V farm in a business environment,
Andi wanted to connect it to you wanted people to be able to log into those machines. You have to put it on an external switch because it's going out to client machines may be in the office or other side of the world. You'd maybe want them on the Internet, whatever as you normally would with a physical machine, basically,
a internal network is when you only want the V EMS to be influenced by the host that's actually running the virtual machines. And then they get their own little network adapter inside that network, and they can share data around that kind of thing
on Dhe. Then Thean Internal One is when you just want the virtual machines just to talk to each other and no one else. You're effectively saying this is your world and nothing else exists.
That's that's when you would use each one. As Eric said in the chat, they can be swapped any time you can literally just go yet. I'll switch it to external switching to internal whatever you want to do. And it will. Usually, unless you want to manually configure anything, it'll just configure itself. Wth E switches the software side of the switching
and the virtual adapters,
they will reconfigure themselves toe check for I P's. If you haven't set them manually, it look for a D. H. C. P on a network. It will set up new adapters if it needs it. All kinds of stuff
so yeah, absolutely. They could be stopped at any time. But there's no hard and fast rule is, too. When you would use one or the other, you just used them as you see fit. If you need it to go external, go external. If you need to go just inside, use an internal network if you just wanna have it so that you can control them on the host.
Andi. If you just want them private,
then you know just the Vienna's talking. Use a private one and then they can't see anything else anyway.
It's all about security at the end of the day,
which, if you guys are members of Siberia, I'm sure you're all up on that security stuff. So, yeah, it's worth knowing.
So yeah, going back to external networks. So the reason why they are so
misunderstood it's probably the best way to explain it is the wording that's used so in the hyper V manager in the interface. It's worded as,
and this is a literal quote and let me read office. Allow management operating system to share this network adapter
so you can see what already I've just quoted that you can see already where the confusion comes from. So it's to allow the management operating system to share this network adapter.
To me, that rings a bell If I didn't know better saying, Oh, the management operating system is gonna share the adapter, but it's gonna have control over the adapter physical adapter. Still
not the case.
So it's all to do with the wording, and Microsoft have promised several times that they're gonna update it. I don't think actually, there's any better way to explain it in a sentence at the moment until they figure something out. But that's kind of where we are with that
now in Power Shell. If you guys have used power shell, you might know about it. It's kind of the new command prompt, basically. So in power shells, new hyphen VM switch Commander.
There's an allowed management operating system parameter,
which is no better. S o. The description of that reads specifies whether the parent partition AII the management operating system
is to have access to the physical nick bound to the virtual switch to be created.
You can see you can see why I I literally had to look at my notes on this one to read,
I've used Hyper V for many, many years, and I still don't remember this word, for. Word is, it makes it way worse in power Shell, with the way explains it.
And what seems to happen far too often
is that people read these and think of the virtual switch on the virtual adapters
like this, like this. So that's That's how I know you can see. I've put a huge ring on it. Please don't take this as gospel. This is not
how it should. It's important
to show you what it doesn't do as much as what it does, because this is the most common misconception of an external network that you will always see when people think that they kind of got it, especially when they're starting out with the hyper V environment
already kind of external network.
That's not how it works. You can see there you've got the virtual machines along the bottom there, and then they go up into a virtual switch, and then the virtual switch connects to the physical adapter of the management operating system, which deals with everything and then that passes it on to the physical network.
It's not true. It's not correct.
it's not. It's totally no accurate on the way that the virtual network stack works is very different now.
Once the virtual switch is bound to a physical adapter,
that doctor is no longer used for anything else. So if you say I'm gonna use it for a virtual switch on, I wanted to be external. I want to connect to this physical network here, and here's my virtual network plugged them together.
It's no longer this physical. Nick can't be used for any other items, including the management operating system,
So T C P I P, which is the way we transfer data Traffic control protocol on Internet protocol is the most other items are removed from it. They're actually disconnected. If you look a virtual once, you've got a physical doctor and you turn on your external network onto it
and go into the options. For if you ever messed around with any network settings, you'll notice that all T c P o P. Stuff gets disabled. That's no mistake.
Do not go in and turn it back on unless you don't want your external network to work.
It could really become plant mistake. I've seen people do it, and they wonder why it's all gone wrong. And then they called me in and I Unfortunately, the business I work for is not cheap on an hourly rate, so they end up really paying for it when effectively, it's a tick box exercise.
Please don't mess for out of the T. C V I. P. The management operating system is quite simply unable to share it. Can't share it out.
If you attempt to bind anything else to that adaptor, it's quite probable that you'll break that virtual switch. It will just won't work anymore.
the management operating system is getting a virtual network adapter off its own
now. This should make a bit more sense in just a second.
Adapter isn't exactly like the adapters that are attached to the other virtual machines. It's not quite as feature rich,
it's nothing at all, like actually sharing the physical adapter in the way that the controls employ
Now. A better term would be connected the management operating system to the virtual switch. That's the easiest way that I could describe it. I sat down for about 15 minutes. I was like, How am I gonna explain it to these guys?
The easiest sentence I could come up with was connect
the management operating system
to the virtual switch. Don't connect it to the physical network port connected to the virtual switch, then connect the entire virtual switch to the physical adapter.
Yeah, so you see where I'm going. Actually, the management operating system sits right next to the virtual machines rather than going on directly to the physical network. On the following image is a much more accurate depiction of what is actually happening. So I'm going to shift this to one side,
and then I'm gonna stick this one up right next to it.
is how an external network works.
So you can see in the bottom left there. The management operating system has its own virtual nick
networking to face card. If he didn't realise what Nick was, I do apologize. I may have missed that.
That's what Nick is
on. And then all of them. So the PM's Andi, the management operating system, connects into this external virtual switch, and then that virtual switch connects to the adapter,
and then the adapter connects out to the rest of your network, whether that's the Internet or your, you know, if you got other machines on your network, this is the correct way.
So you're not using the management operating system to manage anything.
The management operating system is literally the same level as the Viet,
so that's that's kind of is treated the same way as the virtual machines. Effectively,
of course, you always have the option to take one or more physical adapters out of the virtual switch. Yes, Eddie is exactly the same as we m where is just understanding it. And obviously because it is the fundamentals course, we want to make sure that I want to make sure that I explain it correctly because I don't want people stumbling through it, especially if you guys are using this for
certification or you're gonna
Maybe you're doing it at work or anything like that. I want you to understand what's going on with the data and why.
But yes, that the absolutely same as the anywhere,
you always have the option to take one or more physical adapters out of the virtual switch.
Now those will be used by the management operating system as normal. So you could have multiple physical adapters. And then you say right, if that adapter is being used for the virtual switch, I'm gonna put a second physical adapter in, and I can connect back to the management operating system, which means you could literally just give all of that too
a ll, that extent of which were switched to one physical adapted to deal with.
And there's not to deal with anything else.
If you do that, then you don't necessarily need to share the virtual switches adapter with the management operating system.
And what I'm going to show you is very quickly.
The layout was how that would look.
So this is where the management operating system wouldn't be connected directly with the virtual switch.
So you've got to adapters in the same management host operating system. What you do is you say, use this physical adapter to run the external network and use this physical adapter to run my management operating system,
and it means that you could dedicate resource is hardly resource is to that virtual switch affected.
That's that. That's how you would do it if you had multiple adapters toe work with Andi in a business environment. Generally you would see this kind of set up, so it's just giving you an idea, an idea of what it shouldn't look like,
what it should look like and then what it looks like when you go a step further.
So hopefully that's not too much, but feel free, absolutely, to ask questions on it if you want. I'll also be taking questions at the end as well, but you'll also be able to see this in action when we go ahead and make things later on.