When do/did I need development tools/kernel source for `open-vm-tools`?

Question

I have been using open-vm-tools, or the equivalent previous name of the package since Debian 5 or Debian 6 instead of the official VMWare tools, as they are less complicated to install and keep up, and have automatic security updates.

Right now I am using Stretch with open-vm-tools 10.1.5 with the kernel 4.9.0-3-amd64.

I used to have installed linux kernel sources and dkms for modules to be compiled for it, since we do disk paravirtualization and mainly network paravirtualization.

However, over time, the development packages, kernel sources and dkms stopped being necessary, also because I think, the linux kernel started being more "vmware-aware".

I still have here three Stretch i386 based VMs, with the kernels, 4.9.0-3-686-pae, 4.8.0-2-amd64 and 4.8.0-2-686-pae. They all have the build-essentials and source module packages installed.

Interestingly enough, only the 4.8.0-2-amd64 has the module compiled at /lib/modules/*/updates/dkms/vmxnet.ko.

Short of deleting packages and not being able to boot, how can I determine if that module is not needed or not?

Bonus question, when did it happen, kernel source and/or open-vm-tools, that it was not mandatory anymore to compile modules, for having the open vmtools working?

Answer 1

The open-vm-tools-dkms in Debian 9 exists only to provide the vmxnet driver; not to confuse with the current vmxnet3 driver every recent VM should utilize.

If you look at the corresponding VM's vmx-file and you find a line like ethernet0.virtualDev = "vmxnet", you'll need the module. In any other case, you don't. Especially if the virtualDev is vmxnet3.

Likewise you can view the configuration of the Ethernet Adapter in question in the corresponding graphical client. Same here: If it's vmxnet3, you don't need the package.

I can't tell when the vmware support modules appeared in the Debian standard kernel, though. With Deb 8, the dkms-directory also contains vmhgfs.ko. If you utilize the host-guest-filesystem feature with your Deb 8-VMs, you'll need open-vm-tools-dkms, too.