No Sandbox Mode

Running workloads without Firecracker

Firecracker provides Nex operators with the confidence of being able to safely and securely run untrusted workloads. However, when developers are iterating over their application code and they want to deploy via Nex during that loop, requiring Firecracker can get in the way. Firecracker will only work on 64-bit Linux machines that have certain virtualization options enabled in the kernel.

Not only does this limit the developer workstations capable of using the sandbox, but there are a number of cloud virtual machine types that do not support this kind of virtualization.

To make this easier during development, and to allow Nex to manage workloads at the edge, on small devices, or even on Windows, you can run Nex in "unsafe" mode by disabling the sandbox.

The following is a configuration file that shows the use of the no_sandbox field. It might look a bit awkward to set no_sandbox to true, but this naming convention was chosen specifically to make it nearly impossible to accidentally launch a Nex node without a sandbox.

Example Configuration File

    "kernel_filepath": "/path/to/vmlinux-5.10",
    "rootfs_filepath": "/path/to/rootfs.ext4",
    "machine_pool_size": 1,
    "cni": {
        "network_name": "fcnet",
        "interface_name": "veth0"
    "machine_template": {
        "vcpu_count": 1,
        "memsize_mib": 256
    "tags": {
        "simple": "true"
    "no_sandbox": true

Production Use

We strongly recommend the use of the Firecracker sandbox when running in production and suggest that unsafe mode should only be reserved for development and testing environments or those environments (e.g. macOS, Windows, edge devices) incapable of running Firecracker.

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