Overview… error diagnostics
The receive-side error check diagnostics, which are available for each received test payload TID value, comprise:
- Lost packets, a running count based on gaps in the sequence numbers.
- Mis-ordered packets, where a packet arrives later than one with a higher sequence number.
- Payload errors, where the packet payload is not an unbroken sequence of incrementing bytes.
The error checks are based on test payloads, they are active while traffic is running, and they do not depend on knowing which port is sending the traffic.
The XenaManager also displays the overall error rate as a 1.2e-9 style number, calculated from the errors and the number of received bytes.
For missing packets there is also a simpler mechanism that simply compares the total number of packets transmitted and received for a particular stream. This requires knowing the source port.
When the source port stops transmitting, the packet counts will stop changing and any difference between the sent and received count is shown as “(TX – RX) packets”.
Note that this requires that both transmit and receive statistics are cleared before traffic is started, or else it will show a non-factual loss. The statistics will automatically be cleared if you use the global “START” button.