The holes are spaced in a repeating pattern every 0.625 inches (15.875 mm) across the vertical height. Three holes per U:
You have a 2U server (3.5 inches tall) leaving a 1mm gap above it. EIA-310-D allows a "stacking tolerance." While 2U equals exactly 3.5 inches, the standard permits a small cumulative gap (typically a few mm) for thermal expansion and insertion ease. That gap is normal. eia310d standard pdf
This article serves two purposes. First, we will guide you on how to legally access the EIA-310-D PDF. Second, we will break down the technical specifications within the standard so you never have to guess about rack unit spacing, mounting hole patterns, or equipment compatibility again. The holes are spaced in a repeating pattern every 0
Minimum 17.75 inches (450.8 mm) 3. Rail Hole Types Covered Under the Standard That gap is normal
