Generally this error message indicates Packet Buffer CRCs, not front panel port CRCs. A CRC check is done as packets are copied in and out of the packet buffer SRAM. Packets with an invalid CRC are dropped by the Supervisor. Good packets are then stored in packet buffer memory. When the CPU gets a packet, it just knows the memory address where the packet is stored and software reads it from there. In software, the software will check the CRC after reading a packet from memory and if the CRC is bad, the software will log an "Invalid CRC message" and drop the packet . A InvalidPacketBufferCRC count is incremented in NVRAM and Syslog Message is logged as well. The log message is rate limited and you will see only one message in a short interval of 5-10mins (time interval could vary depending on software release). It is normal in any enviroment to get a few InvalidPacketBufferCRCs every few days for the same reason there are PMPEs. However, the InvalidPacketBufferCRCs is incrementing steadily or if the count is in the thousands , then there may be faulty SRAM or other faulty component on the Supervisor. The Power-On Self Test (POST) will check for possible fauty SRAM failures; however, the POST Test is not 100% conclusive for intermittant SRAMs failures. Another possible issue for serveral InvalidPacketBufferCRCs is CSCdt80707 and CSCdu48749 if code version is not 5.5.10 or higher, or 6.2.3 and higher
Note: The count in NVRAM is the total number of InvalidPacketBufferCRCs packets that were received by the CPU since bootup.
We are pleased to announce availability of Beta software for 16.6.3.
16.6.3 will be the second rebuild on the 16.6 release train targeted
towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are
looking for early feedback from customers befor...
Introduction Featured Speakers Luis Espejel is the Telecommunications
Manager of IENova, an Oil & Gas company. Currently he works with Cisco
IOS® and Cisco IOS XE platforms, and NX to some extent. He has also
worked as a Senior Engineer with the Routing P...
In this session you can learn more about Layer 3 multicast and the best
practices to identify possible threats and take security measures. It
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