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New Member

PIX 515 interface overruns

Running PIX 7.0(1)5

On one of the Ethernet interfaces constant overrun errors are being reported and packets are apparently being dropped. There are no other types of errors being logged. The speed and duplex are matched to the switch port and there are multiple VLANs on the port which is configured as a trunk on the switch. The switch is reporting only about 1.7 Mbs throughput. Other interfaces on the PIX are passing similar amounts of traffic, but are not reporting any errors.

Any suggestions as to the cause of these errors or actions that could be taken to correct this would be greatly appreciated.



Re: PIX 515 interface overruns

Overruns appear in the output of the show interface command when the receiver hardware is unable to hand received data to a hardware buffer because the input rate exceeds the receiver's ability to handle the data.

This occurs due to a limitation of the hardware. Overruns occur when the internal First In, First Out (FIFO) buffer of the chip is full (and incoming traffic still coming in in large amount) but still trying to handle incoming traffic. The serial controller chip has limited internal FIFO.



New Member

Re: PIX 515 interface overruns

Thanks, I read that in the manual as well....

As I said... the data rate going to the interface is very low... only about 1.5 Meg... there are other interfaces on the same PIX that are handling similar or higher throughput with no errors.

Any other thoughts?