hashicorp/nomad · error

Error tailing file: %v

Error message

Error tailing file: %v

What it means

nomad alloc fs CLI error from the tail (-tail) path: AllocFS().ReadAt or followFile from OriginEnd failed while streaming the requested slice of the allocation file; the underlying API error is wrapped and printed.

Source

Thrown at command/alloc_fs.go:335

			offset = file.Size
		}

		if follow {
			r, readErr = f.followFile(client, alloc, path, api.OriginEnd, offset, numLines)
		} else {
			// This offset needs to be relative from the front versus the follow
			// is relative to the end
			offset = file.Size - offset
			r, readErr = client.AllocFS().ReadAt(alloc, path, offset, -1, nil)

			// If numLines is set, wrap the reader
			if numLines != -1 {
				r = NewLineLimitReader(r, int(numLines), int(numLines*bytesToLines), 1*time.Second)
			}
		}

		if readErr != nil {
			readErr = fmt.Errorf("Error tailing file: %v", readErr)
		}
	}

	if r != nil {
		defer r.Close()
	}
	if readErr != nil {
		f.Ui.Error(readErr.Error())
		return 1
	}

	_, err = io.Copy(os.Stdout, r)
	if err != nil {
		f.Ui.Error(fmt.Sprintf("error tailing file: %s", err))
		return 1
	}

	return 0

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Confirm the file exists and the requested offset is within the file size
2. Check allocation/client connectivity and that the task is still running
3. Reduce -n/-c values or retry if the file rotated during the read

When it happens

Trigger: Thrown at command/alloc_fs.go:335 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/2a0bdf348cb07213. Report an issue: GitHub.