Core issue
The complete error message is:
%OIR-6-DOWNGRADE_EARL: Module [dec] DFC installed is not identical to system DFC and will perform at current system operating mode.
This message indicates that the Distributed Forwarding Card (DFC) module is at a higher hardware version than the level of the system DFC. The DFC module operates at the same level as that of the system DFC.
The term "system DFC" is actually the Policy Feature Card (PFC) 3 (WS-F6K-PFC3BXL). These restrictions apply to a configuration with a PFC3BXL and these DFCs:
- PFC3BXL and DFC3A PFC3BXL functionality is restricted by the DFC3A: after a reload with a DFC3A-equipped module installed, the PFC3BXL functions as a PFC3A.
- PFC3BXL and DFC3B PFC3BXL functionality is restricted by the DFC3B: after a reload with a DFC3B-equipped module installed, the PFC3BXL functions as a PFC3B.
- PFC3BXL and DFC3BXL There are no restrictions.
The PFC3 is the ASIC-based forwarding engine daughtercard for the Sup720; the DFC3 is the ASIC-based forwarding engine daughtercard for various fabric-enabled linecards. The PFC3 has three different versions: A, B, and BXL.
Since these versions are all within the same generation, it is possible that these three versions can co-exist within the same chassis with similar operation. However, given that there are functional differences between them, a system with a mixture of forwarding engines only operates with the capabilities of the least-capable forwarding engine in the chassis.
You cannot allow each forwarding engine to operate independently in its own mode BXLs running in BXL mode, Bs in B mode, and so on within the same chassis is not allowed. This is because forwarding tables cannot be synchronized if each PFC3/DFC3 is allowed to have different capabilities within the same system.
Resolution
This message is informational only and indicates no problem for the operation of the system.
There is no way to upgrade the revision of the PFC3 on the field. This is performed automatically by the system itself.
In short, this message is produced because the PFC3BXL has to fall back to PFC3A mode because the PFC/DFC revisions in all modules are not the same.
