Cisco IGX 8400 Series Switches

Field Notice 980514: UFM-U Firmware Y.A.A or UFM-C Firmware Z.A.E. or Earlier Do Not Pass Frame Lengths of 5 Bytes or Less

May 13, 1998

Bug Details

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View bug details for CSCdj49811 (registered customers only) (UFM-C and UFM-U).

Products Affected

IGX Universal Frame Relay Module U (UFM-U) and IGX-UFM-C

Problem Description

The UFM-U and UFM-C equipped with firmware Y.A.A or Z.A.E, respectively, discard frames of 5 bytes or less at the ingress to the port. This restricts the UFM Frame Forwarding function to protocols that do not use frames shorter than 6 bytes.

Problem Symptoms

The symptoms include ingress frame discards (use the dspchstats <slot.port.dlci> and dspportstats <slot.port> commands to observe discards), failed links on SNA connections, and data links that come up and then drop other types of data discontinuities.



The solution is to upgrade the firmware on the UFM-C or UFM-U to support short frame sizes. The correct firmware to load on the IGX-UFM-C is Z.A.F or later. The correct firmware to load on the IGX-UFM-U is Y.A.B or later.


The workaround is to use the IGX Frame Relay Module (IGX-FRM) or IGX-FRM-31 until the UFM-C or UFM-U can be upgraded.


Obtain the UFM-C or UFM-U firmware from CCO by visiting URL: Using your CCO account User ID and password to log in, go to Software and Support, then to the Software Center. Download UFM-C firmware Y.A.B or later and/or download UFM-U firmware Z.A.F or later.

Related Field Notice

Field Notice 980515 ALM/B with Firmware C.B.C or Earlier Cannot Pass Frame Lengths of 6 Bytes or Less.

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

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