2.2.1 CPC drawer interconnect topology  Figure 2-10 Maximum CPC drawer SMP connections (rear view) Table 2-2 CPC drawer installation order and position  The CPC drawers that are installed in Frame A and Frame B are populated from bottom to  top. The order of CPC drawer installation is listed in Table 2-2. a. CPC3 and CPC4 are factory installed only (no field MES available) CPC drawer installation in the A frame is concurrent. Non-disruptive addition of CPC1 or  CPC2 drawers is possible in the field (MES upgrade) if the reserve feature (FC 2271 or FC  2272) is present. Concurrent drawer repair requires a minimum of two drawers. The point-to-point SMP connection topology for CPC drawers is shown in Figure 2-10. Each  CPC drawer communicates directly to all of the other CPC drawers SC SCM (L4 cache) by  using point-to-point links. Chapter 2. Central processor complex hardware components  45 CPC drawer$^{a}$  CPC0 CPC1 CPC2 CPC3 CPC4 Installation order First Second Third Fourth Fifth Position in Frame A A10B A15B A20B B10B B15B CP C4 CPC3 CP C2 CPC 1 CP C0