abiosoft/colima · error

error backing up existing file: %w

Error message

error backing up existing file: %w

What it means

In the no-sudo branch of `colima nerdctl install` (taken when /usr/local/bin is writable OR a custom --path is given), an existing target file is first backed up with os.Rename(path, path+".moved"). This error wraps a rename failure: the containing directory is not actually writable, the file is locked, or the custom path's directory does not exist.

Source

Thrown at cmd/nerdctl.go:127

			var values = struct {
				ColimaApp string
				Profile   string
			}{
				ColimaApp: osutil.Executable(),
				Profile:   config.CurrentProfile().ShortName,
			}
			buf, err := util.ParseTemplate(nerdctlScript, values)
			if err != nil {
				return fmt.Errorf("error applying nerdctl script template: %w", err)
			}

			// /usr/local/bin writeable i.e. sudo not needed
			// or user-specified install path, we assume user specified path is writeable
			if nerdctlCmdArgs.usrBinWriteable || nerdctlCmdArgs.path != nerdctlDefaultInstallPath {
				if exists {
					if err := os.Rename(nerdctlCmdArgs.path, nerdctlCmdArgs.path+".moved"); err != nil {
						return fmt.Errorf("error backing up existing file: %w", err)
					}
				}
				if err := fsutil.MkdirAll("/usr/local/bin", 0755); err != nil {
					return nil
				}
				return os.WriteFile(nerdctlCmdArgs.path, buf, 0755)
			}

			// sudo is needed for the default path
			log.Println("/usr/local/bin not writable, sudo password required to install nerdctl binary")
			if exists && !nerdctlCmdArgs.isColimaScript {
				c := cli.CommandInteractive("sudo", "mv", nerdctlCmdArgs.path, nerdctlCmdArgs.path+".moved")
				if err := c.Run(); err != nil {
					return fmt.Errorf("error backing up existing file: %w", err)
				}
			}
			// prepare dir
			{

View on GitHub (pinned to c3a5f9184d)

Solutions

1. Ensure the parent directory of --path exists and is writable: mkdir -p the dir and touch a probe file
2. Use the default path and let the sudo flow handle it (drop --path), or fix the directory permissions
3. Pre-move the old file yourself (mv <path> <path>.moved) and re-run `colima nerdctl install --force`

Example fix

# before
$ colima nerdctl install --path /opt/bin/nerdctl
error: error backing up existing file: rename ...: no such file or directory

# after
$ sudo mkdir -p /opt/bin
$ colima nerdctl install --path /opt/bin/nerdctl --force

// verify rename-ability of the target dir before install
func dirWritable(dir string) bool {
    f, err := os.CreateTemp(dir, ".colima-probe-*")
    if err != nil {
        return false
    }
    return os.Remove(f.Name()) == nil
}

if !dirWritable(filepath.Dir(path)) {
    // mkdir -p the dir, chmod it, or switch to the default sudo flow
}

if err := installCmd.Execute(); err != nil {
    if strings.Contains(err.Error(), "error backing up existing file") && errors.Is(err, fs.ErrPermission) {
        // pre-move the file manually or fix dir permissions, then retry
    }
}

When it happens

Trigger: A custom --path whose parent directory does not exist (rename fails with ENOENT); --path pointing into a read-only mount; the writability probe passing but SIP/permissions still denying rename on macOS; antivirus/file-watcher holding the file open.

Common situations: `colima nerdctl install --path ~/some/missing/dir/nerdctl`; systems where /usr/local/bin ownership changed after the probe; corporate endpoint protection locking new executables.

Related errors

• %s exists, use --force to replace
• error reading ssh config: %w
• error modifying %s: %w
• error preparing to copy VM: %w
• config missing for colima profile '%s': %w

AI-assisted analysis of abiosoft/colima@c3a5f9184d (2026-08-15). Data as JSON: /api/errors/fcd52bc2867c2a98. Report an issue: GitHub.