Hyper-V Default switch IP address range change. Ver 1809 Build 17763.1

southernprogrammer Thanks, gived myself permission to tweak a litlle you script to update all my vmdomains's ip also, work like a charm.

I also think the behavior of the default adapter is not logical, and i personaly see it as a bug, i hope it get fixed since i am migrating from VmWare to Hypre-V, streamlining my setup accross multiple device is better without scripts...

HotCakeX I'm talking about accessing a url that is hosted inside the guest.

If doing development you could do remote debugging on your host while having your environment on your guest.

Thanks, but Hyper-V VMs with enhanced session allow drag and drop between guest and host.

or is the script for a specific situation only?

If you just need to access resources on your guest from the host, you could just have a powershell script that you can run on the host after launching the VM.

Replace 'BryanDev' with the name of your VM and replace "weirdalvm.3-gis.com" with your desired url you want to access the resource with.

Run as administrator

$result = get-vm -Name BryanDev | Select -ExpandProperty Networkadapters | Select IPAddresses | ft -hidetableheaders | Out-String
$result = $result.Split(",")[0].Trim().Replace("{", "").Replace("}", "")


function setHostEntries([hashtable] $entries) {
    $hostsFile = "$env:windir\System32\drivers\etc\hosts"
    $newLines = @()

    $c = Get-Content -Path $hostsFile
    foreach ($line in $c) {
        $bits = [regex]::Split($line, "\s+")
        if ($bits.count -eq 2) {
            $match = $NULL
            ForEach($entry in $entries.GetEnumerator()) {
                if($bits[1] -eq $entry.Key) {
                    $newLines += ($entry.Value + '     ' + $entry.Key)
                    Write-Host Replacing HOSTS entry for $entry.Key
                    $match = $entry.Key
                    break
                }
            }
            if($match -eq $NULL) {
                $newLines += $line
            } else {
                $entries.Remove($match)
            }
        } else {
            $newLines += $line
        }
    }

    foreach($entry in $entries.GetEnumerator()) {
        Write-Host Adding HOSTS entry for $entry.Key
        $newLines += $entry.Value + '     ' + $entry.Key
    }

    Write-Host Saving $hostsFile
    Clear-Content $hostsFile
    foreach ($line in $newLines) {
        $line | Out-File -encoding ASCII -append $hostsFile
    }
}

$entries = @{
    'weirdalvm.3-gis.com' = $result
};

setHostEntries($entries)

HotCakeX 

Very informative thread for this newb.  Like many, I'd consider the behavior of the default switch a bug and not an enhancement. 

1) Installed automatically (not optional).
2) Can't be removed.

3) Can't be modified.
4) No persistent state except unconfigured.
5) Defaults to "Public" on a Domain machine and reconfiguration of state doesn't stick.

VBox and VMWare user attempting to learn Hyper-V and decipher the lack of logic in the above configuration.

Because it's "Public" or doesn't allow the option of a network type selection the Default Switch kills PowerShell WinRM and MS Admin Center on my domain, even when all VMs are using a second manually configured external switch and there is nothing using it - it's still in the registry in the default default configuration after reboot and PowerShell DSC is useless with the Default Switch registering.

I've read the arguments that it's "for amateurs" etc and there to make networking easy.  My experience is exactly the opposite, that it's inexplicably configured to keep professionals from accomplishing their work. It breaks workflows that would otherwise be successful and that is a substantive meaning of a 'bug' in the software.

I've temporarily gone back to VMWare, which works flawlessly managing my virtual lab because default switch just doesn't work in my situation. 

If someone can, please help me find workarounds to the 5 points above I'd greatly appreciate both your time and the knowledge.  Very frustrating to have a simple configuration be this difficult to get working. 

FYI - problems listed above are on 1909.

Thanks

HotCakeX 

Every time I boot, launch anything related to Hyper-V or sneeze.

HotCakeX 

Using anything will not make Default Switch to disappear. It confuses my AV even when no virtual machines are running.

HotCakeX 

I have another silly problem with this default switch. Since it changes its parameters all the time, my antivirus every time thinks it is a new network, and asks me what to do with it. It causes distractions, but the worst part is that it blocks all network on boot until I answer, causing network disks to not mount, which causes unrelated apps to not load properly and so on.

I am trying to figure it out with AV support, but I doubt they will resolve it soon, so I will have to use less optimal antivirus on my PC.

HotCakeX Here I had another chance on completely unrelated PC (different hardware, different location, different networking settings and environment, different users, not in domain, etc.) Same set of initial errors.

Trying to create external switch in GUI:
"Error applying Virtual Switch Properties changes
Adding ports to the switch 'External Switch' failed
The operation was passed a parameter that was not valid."

Trying via PowerShell command ("New-VMSwitch -Name "External VirtualSwitch" -NetAdapterName "Killer e2200 GbE NIC" -AllowManagementOS $True"):
"New-VMSwitch : Failed while adding virtual Ethernet switch connections.
External Ethernet adapter 'Killer e2200 Gigabit Ethernet Controller #2' is already bound to the Microsoft Virtual Switch protocol."

So I tried "easy" solution first, and in NIC Properties unchecked option:
"Hyper-V Extensible Virtual Switch"
(And rebooted PC)

Luckily, on this PC when I tried to create external switch in GUI after reboot everything went ok. Didn't have to use the "nuke" option this time.

But still, quite annoying. And (at least in my case) on PCs that I regularly use I have all of them throwing this or that error. I love MS, but sometimes I hate it as well...

Cheers!

HotCakeX It seems you are right, I'm sorry... But it seems that Microsoft still has a related bug, as I had (and have) the same issue on multiple PCs, and looking at Microsoft forums, I'm not alone.

There are several errors when trying to create External adapter, in my case, always on newer Win10 with Default Switch present (Windows 10 version 1709 or newer), so I (maybe mistakenly?) believe these to be related.

First error:

"the operation was passed an invalid parameter"

Complementary error (from Powershell's New-VMSwitch commandlet):

"Adapter is already bound to the Microsoft Virtual Switch protocol"

Proposed solutions:

https://social.technet.microsoft.com/Forums/azure/en-US/3272e5cc-e3d7-44a9-8da8-1a50a80afdf0/external-ethernet-adapter-is-already-bound-to-the-microsoft-virtual-switch-protocol?forum=winserverhyperv

Network and Sharing (Win7)/Network (Win 10)
Change adapter settings/options
Right-click Local Area Connection
Go to Properties
Scroll to the bottom of the list
Uncheck "Hyper-V Extensible Virtual Switch" option

Alternative:

The nuclear option that works with Windows Core is using netcfg to wipe out all your networking settings and re-initialize the network card drivers.

#WARNING! DANGER! THIS WILL DELETE ALL YOUR NETWORKING SETTINGS!
netcfg -d

Second error, after I did uncheck Hyper-V from my physical NIC and rebooted:

Tried to create External switch via PowerShell again

New-VMSwitch -Name "External VirtualSwitch" -NetAdapterName "Ethernet" -AllowManagementOS $True

Error:

"bind failed: {Access Denied} A process has requested access to an object, but has not been granted those access rights"

Proposed solutions:

https://social.technet.microsoft.com/Forums/windowsserver/en-US/84f413dc-2da0-44c0-928d-70b7a6c0404b/hyperv-virtual-switch-manager-cannot-create-an-external-switch?forum=winserverhyperv

Hi, I solved this by: In PowerShell type: netcfg -d This WILL DELETE all network adapters AND network SETTINGS! Physical adapters will NOT be LOST. Then i restored my network settings and created new External Virtual Switches.

So since both errors proposed "netcfg -d" I did that, rebooted, naturally now I have two Default Switches that I will just need to ignore, but now I can create External Switch without errors (both in GUI and PoSh), and use them as usual (pre-Win10/1709 times).

I do still stand by the fact that a) Default Switch should be OPTIONAL (can be setup as default behavior, but should have option to be removed) and b) that Microsoft somehow at the same/similar time introduced related bugs that provoke issues with creation of External switches.

I'm kinda happy now that I have my External switch running again, and will just have to live with the unneeded default switches lingering there in the background forever. Maybe you didn't have issues for a mix of reasons (maybe you did not upgrade all the way from initial Win10, or maybe you have other inactive adapters that are poluted by this bug but you don't use them so never noticed, or - you're just lucky).

Hopefully the links to two threads and the copied proposed solutions will help someone somewhere when they pop onto this thread through web search, if it helps just one more person I'll be happy.

Cheers!

Guy, kudos for dragging this conversation for so long... And I see each has their own set of arguments.

But what HotCakeX keeps forgetting is to tell the whole truth about his setup, and whole truth (and main issues) with DefaultSwitch.

Yes, DefaultSwitch is all fine for my granny to put a VM on her Win10 and put it online. But what is not ok is:

- that DefaultSwitch permanently grabs one ethernet connection for it's own purposes

- this connection may well be only one, for example, on workstation PC which isn't on WiFi, and doesn't have 2 LAN adapters

- cannot be removed

- prevents you from setting up second virtual switch / adapter on same interface as it is already binded to DefaultSwitch

- no workaround as DefaultSwitch keeps recreating itself on each reboot (so if you remove it, it will be there next reboot, if you disable it, it will be re-enabled, etc)

All is good, I have several clusters I can use to put VMs on them, with all dedicated connections, and all. But sometimes I just want/need to use a small VM on my PC, and I want it to KEEP the IP addresses same through reboots. There is simply NO REASON for it to be recreated every time, my local networks don't change, if 172.18.123.15 isn't conflicting on one reboot, it's not gonna conflict on next reboot. Yet - Win10 will still recreate it if I reboot, and with new IP range. There is also NO REASON for DefaultSwitch to be unremovable. We had Hyper-V before Default Switch, and on client PCs, and it worked just fine. Sure, make DefaultSwitch default config, my grandma really likes showing CentOS on her VMs from time to time, but give the option for REAL USERS (aka developers, sysadmins, etc) to remove/disable the DefaultSwitch garbage and use Hyper-V same way we've used it for years on our PCs. Instead, we have to keep Googling and hoping something will change with time. Or just endure the bad state of things, and use "real servers" just so we can have a small VM for whatever purposes we need it.

Btw, those that want to evaluate software sometimes want to make a small proof of concept on their workstation, without it requiring 2 more teams to allow you to a) put these VMs on their clusters b) create temporary networks for you to test something for a week or two.

Let me go back to the main thing that hurts a lot of people... HotCakeX you said you have your whole setup with home router and cheap 20$ WiFi adapter... yet you are forgetting to tell people that you also have second built-in adapter that you have in same PC/laptop. One that DefaultSwitch grabbed and "polluted" forever, and then you are using a 20$ adapter as your external adapter. That's paying 20$ for Microsoft's decision to make DefaultSwitch UNREMOVABLE.

Anyway, thanks for again confirming that MS still didn't fix this properly (and will probably stay broken as is), I'll revisit this in a year or so again, just to check if I can finally get back to the functionality I had with Windows 7, without buying new adapters, setting up new test WiFi environments, laying down new cables or buying new switches, just so my workstation could have a VM with ... predictable IP.

GlaucomaPredator  I have not found a way to permanently delete the Default Switch. I've been just ignoring it for now.

mlmathews The problem is not being able to destroy the old switch. How did you manage that?

HotCakeX 

I don't have time to list everything I've noticed, but I'll give you a couple of networking examples.

In VMware both the NAT and host-only networks have a virtual DHCP server that's configurable.

Another example is in VMware a bridged virtual adapter can be set to automatically select a physical adapter to bridge...so if you are developing on a laptop it will automatically switch between wifi and ethernet.