{"record":{"id":"99174fd89339536b","repo":"hashicorp/packer","slug":"checksum-failed-to-open-file-for-checksum-s","errorCode":null,"errorMessage":"Checksum: failed to open file for checksum: %s","messagePattern":"Checksum: failed to open file for checksum: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"packer/plugin-getter/checksum.go","lineNumber":86,"sourceCode":"}\n\n// ParseChecksum expects the checksum reader to only contain the checksum and\n// nothing else.\nfunc (c *Checksummer) ParseChecksum(f io.Reader) (Checksum, error) {\n\tres := make([]byte, c.Hash.Size())\n\t_, err := hex.NewDecoder(f).Read(res)\n\tif err == io.EOF {\n\t\terr = nil\n\t}\n\treturn res, err\n}\n\n// ChecksumFile compares the expected checksum to the checksum of the file in\n// filePath using the hash function.\nfunc (c *Checksummer) ChecksumFile(expected []byte, filePath string) error {\n\tf, err := os.Open(filePath)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"Checksum: failed to open file for checksum: %s\", err)\n\t}\n\tdefer f.Close()\n\terr = c.Checksum(expected, f)\n\tif cerr, ok := err.(*ChecksumError); ok {\n\t\tcerr.File = filePath\n\t}\n\treturn err\n}\n\nfunc (c *Checksummer) Sum(f io.Reader) ([]byte, error) {\n\tc.Hash.Reset()\n\tif _, err := io.Copy(c.Hash, f); err != nil {\n\t\treturn nil, fmt.Errorf(\"Failed to hash: %s\", err)\n\t}\n\treturn c.Hash.Sum(nil), nil\n}\n\nfunc (c *Checksummer) Checksum(expected []byte, f io.Reader) error {","sourceCodeStart":68,"sourceCodeEnd":104,"githubUrl":"https://github.com/hashicorp/packer/blob/eb36e3c3e48a036f3e8cc94087636ee72e1303c9/packer/plugin-getter/checksum.go#L68-L104","documentation":"Checksummer.ChecksumFile opens the downloaded plugin file to verify its checksum and returns this error when os.Open fails. It wraps the underlying OS error, so it almost always means the file does not exist, the path is wrong, or the process lacks read permission.","triggerScenarios":"Called from InstallLatest (via Get) on the downloaded plugin binary path when the file wasn't actually downloaded, was moved/deleted between download and verification, or the path has wrong permissions/symlink issues.","commonSituations":"Plugin download partially failed leaving no file; disk full or antivirus quarantined the binary; running packer as a user without read access to the plugin cache directory; concurrent installs racing on the same file.","solutions":["Re-run `packer init` / the install so the plugin file is re-downloaded.","Check the file exists at the reported path (ls) and that permissions allow reading.","Clear the plugin cache directory (e.g. ~/.packer.d/plugins) and retry.","Check disk space and that no antivirus/EDR is removing downloaded binaries."],"exampleFix":null,"handlingStrategy":"validation","validationCode":"if _, err := os.Stat(filePath); err != nil {\n    return fmt.Errorf(\"plugin file %s missing before checksum: %w\", filePath, err)\n}\nerr := cs.ChecksumFile(expected, filePath)","typeGuard":null,"tryCatchPattern":"if err != nil {\n    var pe *fs.PathError\n    if errors.As(err, &pe) && errors.Is(pe.Err, fs.ErrNotExist) { /* re-download the plugin */ }\n}","preventionTips":["Ensure the download step completed and returned success before checksumming.","Check disk space and permissions on the plugin cache directory.","Clear a corrupt plugin cache and re-run installs rather than reusing stale files."],"tags":["filesystem","checksum","plugin-install"],"backgroundTag":"file-not-found","analyzedSha":"eb36e3c3e48a036f3e8cc94087636ee72e1303c9","analyzedAt":"2026-09-05T13:20:43.127Z","contentChangedAt":"2026-09-05T13:20:43.127Z","schemaVersion":2},"datasetVersion":"2026-09-12T17:17:11.597Z"}