Beginning Cisco NX-OS Release 7.0(3)I7(7) TCP based interface statistics streaming is supported on Cisco Nexus 3500 series switches. This feature, based on TCP request response model, provides more granular interface statistics information at 10–15 millisecond intervals.

The TCP service listens to port 7891, over localhost interface allowing applications that run on the switch to capture statistics. The TCP server responds with statistics data to requests that the client initiates. Any custom TCP client application can make a connection and request for statistics. The feature provides the following per port statistical information:

• Tx Pkts

• Tx Bytes

• Rx Pkts

• Rx Bytes

The statistical information is displayed in the following format:

 ------------------------------------------------
 | timestamp             |           |          |
 | ----------------------| num_ports | counters |
 | tv_sec | tv_nsec      |           |          |
 | ----------|-----------|-----------|----------|
 | 8 - bytes | 8 - bytes | 4 - bytes |       || |
 --------------------------------------------||--
                                             ||
                                             \/
 -------------------------------------------------------------
 | interface_name | Tx Pkts | Tx Octets | Rx Pkts | Rx Octets |
 |-------------------------------------------------------------
 | 24-bytes       | 8-bytes | 8-bytes   | 8-bytes | 8-bytes   |
 |------------------------------------------------------------
 | 24-bytes       | 8-bytes | 8-bytes   | 8-bytes | 8-bytes   |
 |------------------------------------------------------------
 | 24-bytes       | 8-bytes | 8-bytes   | 8-bytes | 8-bytes   |
 --------------------------------------------------------------
 | 24-bytes       | 8-bytes | 8-bytes   | 8-bytes | 8-bytes   |
 --------------------------------------------------------------
 | 24-bytes       | 8-bytes | 8-bytes   | 8-bytes | 8-bytes   |
 --------------------------------------------------------------
 ...........................................................
 ...........................................................

 --------------------------------------------------------------
 | 24-bytes       | 8-bytes | 8-bytes   | 8-bytes | 8-bytes   |
 --------------------------------------------------------------

TCP based interface statistics monitoring has the following configuration guidelines and limitations:

• TCP based interface statistics polling works with CLI/SNMP polling.

• TCP based interface statistics monitoring feature is enabled by default.

• The TCP server listens to port 7891 and it does not accept TCP connections from outside the switch.

• TCP clients that are running within the switch can only leverage the advantages of this feature.

• Only one TCP session is allowed at a time.

• Client applications can poll statistics at 5ms to 10ms intervals. USD process utilization goes above 40% for poll requests below 5ms intervals.