Users Guide

● IOM placement for each scalable fabric must be the same within the same chassis. For example, if the FSE for the first
scalable fabric is in Slot A1, then the second FSE must be in slot B1 in the same chassis, and so on.
● For chassis that only contain FEMs, all four FEMs must connect to the same chassis with the FSEs. The fabric B FEMs
cannot be connected to FSEs in a different chassis as the fabric A FSEs.
Recommended connection order
Any QSSFP28-DD port on the MX9116n can be used for any purpose. The table below describes the recommended port order
for connecting chassis with Fabric Expander Modules (FEMs) to the FSE. The table contains references IOMs in fabric A, but
the same guidelines apply to IOMs in fabric B.
Table 19. Recommended port order for connecting FEM to FSE
Chassis FSE Port (Phys Port)
1 & 2 FSE Port 1 (17/18)
3 FSE Port 7 (29/30)
4 FSE Port 2 (19/20)
5 FSE Port 8 (31/32)
6 FSE Port 3 (21/22)
7 FSE Port 9 (33/34)
8 FSE Port 4 (23/24)
9 FSE Port 10 (35/36)
10* FSE Port 6 (25/26)
*—By default, the port group 10 is not configured to support a FEM. If you want to connect a FEM to this port, use the OME -
Modular interface to set the port mode to Fabric Expander.
NOTE:
The port groups, 6, 11, and 12 (physical ports 27/28, 37/38, 39/40), can be used for additional uplinks, ISLs, rack
servers, and so on.
78 MX Scalable Fabric architecture