What causes "failed to rename ASIF image from %#q to %#q: %w" in lima-vm/lima?

Delete the pre-existing conflicting file at `path` and retry

failed to rename ASIF image from %#q to %#q: %w

Error message

failed to rename ASIF image from %#q to %#q: %w

What it means

After creating an ASIF image, NewASIF handles a diskutil quirk: some versions create the file with a `.asif` suffix appended. This error occurs when `os.Rename(path+".asif", path)` fails while fixing up that quirk. It wraps the OS-level rename failure.

Source

Thrown at pkg/imgutil/nativeimgutil/asifutil/asif_darwin.go:30

	"os"
	"os/exec"
	"strconv"
	"strings"

	"github.com/lima-vm/lima/v2/pkg/plist"
)

// NewASIF creates a new ASIF image file at the specified path with the given size.
func NewASIF(path string, size int64) error {
	createArgs := []string{"image", "create", "blank", "--fs", "none", "--format", "ASIF", "--size", strconv.FormatInt(size, 10), path}
	if err := exec.CommandContext(context.Background(), "diskutil", createArgs...).Run(); err != nil {
		return fmt.Errorf("failed to create ASIF image %#q: %w", path, err)
	}
	if _, err := os.Stat(path); errors.Is(err, os.ErrNotExist) {
		if _, err2 := os.Stat(path + ".asif"); !errors.Is(err2, os.ErrNotExist) {
			// diskutil may create the file with .asif suffix
			if err3 := os.Rename(path+".asif", path); err3 != nil {
				return fmt.Errorf("failed to rename ASIF image from %#q to %#q: %w", path+".asif", path, err3)
			}
		}
	}
	return nil
}

// NewAttachedASIF creates a new ASIF image file at the specified path with the given size
// and attaches it, returning the attached device path and an open file handle.
// The caller is responsible for detaching the ASIF image device when done.
func NewAttachedASIF(path string, size int64) (string, *os.File, error) {
	if err := NewASIF(path, size); err != nil {
		return "", nil, err
	}
	attachArgs := []string{"image", "attach", "--noMount", path}
	out, err := exec.CommandContext(context.Background(), "diskutil", attachArgs...).Output()
	if err != nil {
		return "", nil, fmt.Errorf("failed to attach ASIF image %#q: %w", path, err)
	}

View on GitHub (pinned to dd909d0973)

Solutions

Delete the pre-existing conflicting file at `path` and retry
Check write permissions on the directory containing the image
Ensure no other process is concurrently creating the same image
If rename keeps failing, manually rename `path.asif` to `path` before retrying the operation

Example fix

// before
_ = os.Remove(diskPath) // stale file blocks rename
err := asifutil.NewASIF(diskPath, size)
// after
if err := os.Remove(diskPath); err != nil && !os.IsNotExist(err) { return err }
if err := asifutil.NewASIF(diskPath, size); err != nil { return err }

Defensive patterns

Strategy: try-catch

Validate before calling

// preflight: ensure target path is free before creating the image
if _, err := os.Stat(path); err == nil { return fmt.Errorf("image path %q already exists", path) }

Try / catch

if err := asifutil.NewASIF(path, size); err != nil {
    if strings.Contains(err.Error(), "failed to rename") {
        os.Remove(path); os.Remove(path + ".asif") // clear stale files, then retry once
    }
    return err
}

Prevention

Remove stale image files from previous failed runs
Avoid concurrent operations on the same image path
Create images in directories with write permission

When it happens

Trigger: NewASIF ran successfully but the produced file is at `path+".asif"`, and the rename back to `path` fails — typically the target exists and cannot be replaced, or a permissions/volume issue prevents the move.

Common situations: A stale file already exists at the target path from a previous failed run; the directory is read-only; cross-volume rename restrictions; concurrent Lima operations racing on the same path.

Related errors

AI-assisted analysis of lima-vm/lima@dd909d0973 (2026-09-01). Data as JSON: /api/errors/40c1a2769eddf2f3. Report an issue: GitHub.