Virtual Machines Automation from Hypervisors using Qemu-Agent on KVM

[KuasarCloud]

ISSUE TYPE

• Feature Idea

COMPONENT NAME

Categorize the issue, API, KVM, HYP, UI

CLOUDSTACK VERSION

Coming versions

SUMMARY

Many of us are using Cloudstack to provide public and private cloud services for our internal teams and clients, so normally we don't handle passwords or ssh key password to access the vm's operating system to orchestrate applications lifecycle. So my proposal is that just like user-data works for the first boot we can register actions or commands that we can apply to client's vm using qemu-agent capabilities in KVM so we leverage services like:

• DBaaS
• Managed Applications
• Improvements on CSK

STEPS TO REPRODUCE

Cloudstack access the hyp where the vm resides and applies commands like:

virsh qemu-agent-command "$VM_NAME" "$COMMAND_JSON"

[DaanHoogland]

@KuasarCloud , this seems like a qemu/libvirt specific feature, any idea if this has similar implementation possibilities for xen/vmware?
At the moment such functionality would be implemented using terraform. Any reason why this would not be acceptable?

[KuasarCloud]

In VMware, we can use VMware Tools or Open VM Tools (an open-source version) to execute commands within the VM. Commands can be sent through the VMware API, but this solution is more limited and depends on the specific version and capabilities of the VMware infrastructure. The functionality to execute specific commands, as qemu-agent would allow, is possible, but it’s not as robust or straightforward as in KVM. Nevertheless, VMware does allow certain administrative commands and interactions with VMs.

In Xen, the functionality is more limited, as there is no direct equivalent to qemu-agent. While we can use xe-guest-utilities to get basic system status information and limited interactions, it doesn’t provide the same flexibility to send specific commands as in KVM.

To achieve something similar in Xen, we would need to implement custom user scripts or use configuration tools like cloud-init to run commands at VM startup. However, this approach only works on the first boot, similar to using user-data.