PPE PPE HW Fault Trap:.* Count.*, PC.*,.*: ipv4_input_set_proto_and_ports

The

message indicates that a trap occurred when the microcode attempted to interpret data past the end of the packet.

When an ipv4_input_set_proto_and_ports event occurs, a message similar to the following is reported:

This can also be seen in connection with this syslog message:

The error occurs at the microcode instruction label ipv4_input_set_proto_and_ports. These instructions extract Layer 4 ports from a packet and place them in an internal context. However, a malformed packet is causing the microcode to read past valid lmem memory, thereby causing a hardware (HW) fault. This can occur when a packet Authentication Header length field points past the end of the packet.

Perform these steps to determine the cause and resolve the problem (if any):

1. Collect the show command output to help determine the cause of this message.

Capture the output to a file (in case you have to open a technical support case). To do this, configure each SSH client/terminal emulator to log your session.

2. Analyze the show command output. Look for any related events that occurred at or just before the ipv4_input_set_proto_and_ports message in the syslog or chassisd outputs.

3. If the message only occurs sporadically, infrequently, or both, the PFE is behaving normally and discarding malformed packets. The log message is cosmetic in this case.

4. If the messages continue regularly, then, during a maintenance window (as it will impact transit traffic), try rebooting the associated FPC with the command

, where # is the number of the FPC referenced in the log message.

5. If these efforts do not resolve the problem, contact your technical support representative to investigate the issue further.

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Prasanna

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