{"record":{"id":"33647501d367105c","repo":"hashicorp/nomad","slug":"couldn-t-read-the-file-information-v-w","errorCode":null,"errorMessage":"Couldn't read the file information %v: %w","messagePattern":"Couldn't read the file information (.+?): %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"client/allocdir/task_dir.go","lineNumber":271,"sourceCode":"\t\t}\n\n\t\t// Create destination directory.\n\t\tdestDir := filepath.Join(t.Dir, dest)\n\n\t\tif err := createDir(t.Dir, dest); err != nil {\n\t\t\treturn fmt.Errorf(\"Couldn't create destination directory %v: %w\", destDir, err)\n\t\t}\n\n\t\t// Enumerate the files in source.\n\t\tdirEntries, err := os.ReadDir(source)\n\t\tif err != nil {\n\t\t\treturn fmt.Errorf(\"Couldn't read directory %v: %w\", source, err)\n\t\t}\n\n\t\tfor _, fileEntry := range dirEntries {\n\t\t\tentry, err := fileEntry.Info()\n\t\t\tif err != nil {\n\t\t\t\treturn fmt.Errorf(\"Couldn't read the file information %v: %w\", entry, err)\n\t\t\t}\n\t\t\thostEntry := filepath.Join(source, entry.Name())\n\t\t\ttaskEntry := filepath.Join(destDir, filepath.Base(hostEntry))\n\t\t\tif entry.IsDir() {\n\t\t\t\tsubdirs[hostEntry] = filepath.Join(dest, filepath.Base(hostEntry))\n\t\t\t\tcontinue\n\t\t\t}\n\n\t\t\t// Check if entry exists. This can happen if restarting a failed\n\t\t\t// task.\n\t\t\tif _, err := os.Lstat(taskEntry); err == nil {\n\t\t\t\tcontinue\n\t\t\t}\n\n\t\t\tif !entry.Mode().IsRegular() {\n\t\t\t\t// If it is a symlink we can create it, otherwise we skip it.\n\t\t\t\tif entry.Mode()&os.ModeSymlink == 0 {\n\t\t\t\t\tcontinue","sourceCodeStart":253,"sourceCodeEnd":289,"githubUrl":"https://github.com/hashicorp/nomad/blob/482b49bf1aec006f089bcfc7e632d8f6ac303e5e/client/allocdir/task_dir.go#L253-L289","documentation":"While iterating dirEntries from os.ReadDir in embedDirs, each entry's stat info is fetched with fileEntry.Info(). This error wraps that Info() failure. Info() typically fails only if the directory entry was removed or became unreachable between ReadDir and Info (ENOENT), or on I/O error.","triggerScenarios":"fileEntry.Info() returns an error during chroot directory embedding — the file inside the host source directory was deleted concurrently, or the underlying filesystem reported an I/O error / EACCES on the parent dir during lstat.","commonSituations":"Concurrent modification of host dirs (package upgrade, tmp cleaner racing the alloc build); corrupted or failing disk (EIO) on a chroot source like /usr or /lib; NFS stale-handle errors on network-mounted sources.","solutions":["Re-run the alloc — this is often a transient race and a fresh chroot build succeeds","Check the wrapped errno: EIO → run filesystem/disk checks (fsck, SMART); ESTALE → remount the network filesystem","Stop processes that mutate chroot source dirs during alloc builds (config management, cron cleanups)","If reproducible on one host, cordon/drain the Nomad client node and investigate host health"],"exampleFix":"# before\nCouldn't read the file information %!s(*os.fileStat=&{...}): lstat /usr/lib/x.so: no such file or directory\n# after\n# hold package manager/tmp cleaner during alloc start, then\n$ nomad alloc restart <alloc>","handlingStrategy":"retry","validationCode":null,"typeGuard":null,"tryCatchPattern":"if err := taskDir.Build(fsi, chroot, username); err != nil {\n    if strings.Contains(err.Error(), \"Couldn't read the file information\") {\n        // transient race or EIO — backoff and retry the chroot build\n        time.Sleep(backoff)\n        return retryBuild(taskDir)\n    }\n    return err\n}","preventionTips":["Avoid mutating chroot source directories (package upgrades, cleanups) while allocs start","Freeze config management runs during client deployments","Monitor disk health (SMART) — repeated Info() EIO means failing hardware","Retry once before paging: most occurrences are transient TOCTOU races"],"tags":["filesystem","chroot","race-condition"],"backgroundTag":"stat-failed","analyzedSha":"482b49bf1aec006f089bcfc7e632d8f6ac303e5e","analyzedAt":"2026-09-04T07:54:14.808Z","contentChangedAt":"2026-09-04T07:54:14.808Z","schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}