Hyper-V for development machines

I like to keep as many of my dev tools off my local machine as possible. Not only does it make reinstalling my base system easier but it also helps improve security - which is especially useful when software publishers like Microsoft start panicking and pull extensions over security fears (ok - that actually was a false positive and Microsoft over-reacted but IDE/editor extensions do have a lot of control and risk attached to them).

Whilst I've historically used VirtualBox to run dev machines I've recently switched over to Hyper-V, what with its native Windows support actually being fairly good.

One issue though is around maintaining a static IP address for the virtual machines.

The default switch attached to VMs is DHCP only and a dynamic IP is assigned. I could go in to my router settings and assign an IP to the specific VM's MAC address but I prefer a solution within the VM.

As such, once I've installed a Debian-derivative of Linux in the VM...

Initial setup

Continue to use Hyper V default switch with DHCP and NAT on the VM - this gets inbound and outbound internet access between guest and host.

Create a new internal only network switch and add the VM to it on the host.

Check which IP range the internal network switch is using on the host. To do this go to network adapters, view additional properties on the internal network adapter and make a note of the gateway IP address (in my case 172.25.208.1) and netmask.

VM setup

SSH into the VM.

Create /etc/netplan/01-netcfg.yaml as root and chmod 600 01-netcfg.yaml.

Note: may have to disable cloud-init if there is a /etc/netplan file for that as by default it reenables DHCP on eth0. Check for presence of cloud-init related file in /etc/netplan. If it's there, disable cloud-init with sudo touch /etc/cloud/cloud-init.disabled

Check which interface is DHCP and which is internal switch by running ip a and matching the interface IP to the range the host internal network adapter is using.

Add the following to /etc/netplan/01-netcfg.yaml, replacing eth0 and eth1 with your relevant interfaces. Replace 172.25.208.2/24 with a suitable static IP within the range specific on the host adapter.

network:
  ethernets:
    eth0:
     dhcp4: false
     addresses: [172.25.208.2/24]
    eth1:
      dhcp4: true

This ensures we maintain DHCP for the default switch and assigns a static IP to the internal switch.

Run netplan apply to apply the settings.

Exit SSH and try and ping the VM static IP from the host to confirm all is working.