Displaying interface statistics

Use the ifstat command

The ifstat command prints per-interface statistics not reported by commands such as netstat. This includes some statistics maintained by the networking code, as well as statistics maintained by the driver and by the networking card.

The output of the ifstat command might contain many fields, because different types of interfaces, for example, Ethernet, Gigabit (GB) Ethernet, FDDI, and ATM, have different statistics.

ifstat syntax

The syntax for the ifstat command is

ifstat [-z] -a | interface

The -z option "zeros" (or clears) the statistics. The -a option lists statistics for all the filer's interfaces. The interface option indicates the type of interface for which you want statistics.

Explanation of interface statistics

Ethernet

The following table describes the statistics in the RECEIVE section of the ifstat command output when you use the command on an Ethernet interface.


Statistic	Meaning
Packets	Number of packets received on the interface.
Bytes	Number of bytes received on the interface.
Errors	Number of errors during Ethernet frame reception, including all kinds of receive errors.
No buffers	Number of received packets dropped due to the unavailability of buffers.
Length err	Number of frames truncated due to the shortage of receive descriptors.
Runt frames	Number of runt frames.
Long frames	Number of frames received that exceeded the maximum Ethernet-specified size of 1,518 bytes.
CRC error	Number of CRC errors that occurred on the received frames.
H/w overflow	Number of frames discarded because of receive FIFO overflow.
Process stop	Number of times the receive process stopped.
List overflow	Number of frames dropped due to the unavailability of descriptors.
Process reset	Number of times the receive process was reset.
Rst frame drops	Number of frames discarded due to the resetting of the receive process.

The following table describes the statistics in the TRANSMIT section of the ifstat command output when you use the command on an Ethernet interface.


Statistic	Meaning
Packets	Number of packets attempted to be transmitted.
Bytes	Number of bytes attempted to be transmitted.
Errors	Number of hardware errors encountered while attempting to transmit.
Collisions	Number of collisions that occurred while transmitting frames.
Late collisions	Number of collisions aborted due to a late collision.
Excess coll	Number of times transmission was aborted due to excessive collisions.
Queue full	Number of times the queue was full.
List full	Number of frames that were dropped due to the unavailability of descriptors.
No carrier	Number of times the carrier signal was not present during transmission.
Underflow	Number of times the transmitter aborted the message because data arrived late from memory.
Defer	Number of times transmission had to be deferred.
Time out	Number of times the transmit jabber timer expired.
Stopped	Number of times the receive process stopped.
List underflow	Number of frames that had to be dropped due to the unavailability of descriptors.
Loss of carrier	Number of times the carrier was lost.
No buffers	Number of times buffers were unavailable.
Requeue	Number of times the frame was requeued due to list underflow.
Threshold up	Number of times the transmit threshold was increased.
Threshold dn	Number of times the transmit threshold was decreased.
Threshold lvl	Current threshold level.

The following table describes the statistics in the DEVICE section of the ifstat command output when you use the command on an Ethernet interface.


Statistic	Meaning
Interrupts	Number of times the Ethernet device interrupted the host.
Resets	Number of times the Ethernet device was reset.

The following table describes the statistics in the LINK INFO section of the ifstat command output when you use the command on an Ethernet interface.


Statistic	Meaning
Auto	Auto-Negotiation state.
Mediatype	Media type, such as twisted pair.
Link Partner	The Auto-Negotiation capability of the remote end. It is unknown if Auto-Negotiation is disabled.
Link State	Link status.

GB Ethernet

The following table describes the statistics in the RECEIVE section of the ifstat command output when you use the command on a GB Ethernet interface.


Statistic	Meaning
Packets	Number of packets received on the interface.
Bytes	Number of bytes received on the interface.
Errors	Number of errors during Ethernet frame reception, including all kinds of receive errors.
Queue full	Number of received packets dropped due to the unavailability of buffers.
Unicast packets	Number of unicast packets received.

The following table describes the statistics in the TRANSMIT section of the ifstat command output when you use the command on a GB Ethernet interface.


Statistic	Meaning
Packets	Number of packets attempted to be transmitted.
Bytes	Number of bytes attempted to be transmitted.
Errors	Number of hardware errors encountered while attempting to transmit.
Collisions	Number of collisions that occurred while transmitting frames.
Unicast packets	Number of unicast packets transmitted.

The following table describes the statistics in the DEVICE section of the ifstat command output when you use the command on a GB Ethernet interface.


Statistic	Meaning
Received errors	Number of errors encountered during reception by the interface.
Transmit errors	Number of errors encountered during transmission by the interface.
Collisions	Number of collisions encountered during transmission by the interface.

FDDI

The following table describes the statistics in the RECEIVE section of the ifstat command output when you use the command on an FDDI interface.


Statistic	Meaning
Packets	Number of packets received on the interface.
Bytes	Number of bytes received on the interface.
Errors	Number of errors during Ethernet frame reception, including all kinds of receive errors.
Queue full	Number of received packets dropped due to the unavailability of buffers.
H/w faults	Number of hardware faults.
SA matches	Number of SA matches.
DA nonmatches	Number of DA non-matches.
PDQ aborts	Number of PDQ aborts.
Invalid lengths	Number of invalid lengths.
Fragments	Number of fragments.
Format errs	Number of frames received that contained an odd number of symbols; that is, the number of non-integral octets.
MAC resets	Number of MAC resets.
CRC Errors	Number of frames received with a bad frame check sequence.
Status Errors	Number of frames received that had the E (error detected) indicator set or a missing E indicator.
Long Frames	Number of frames received that were larger than the maximum legal size.
Short Frames	Number of short frames received.
Copied buffers	Number of copied buffers.
No buffers	Number of times there were insufficient buffers.
LLC errors	Number of LLC errors.
Blk check errs	Number of block check errors.
Length errors	Number of length errors.
Overruns	Number of times that the interface received a frame loss indication from the hardware on the interface.

The following table describes the statistics in the TRANSMIT section of the ifstat command output when you use the command on an FDDI interface.


Statistic	Meaning
Packets	Number of packets attempted to be transmitted.
Bytes	Number of bytes attempted to be transmitted.
Errors	Number of hardware errors encountered while attempting to transmit.
Queue full	Number of received packets dropped due to unavailability of buffers.
No buffers	Number of times buffers were not available.
No buf resets	Number of times the process was reset due to the unavailability of buffers.
No descriptors	Number of times descriptors were unavailable.
I/f down	Number of times the interface was down.
Underruns	Number of times an underrun occurred because the interface's transmit FIFO became empty due to insufficient memory. That is, the device tried to transmit but could not get data into memory fast enough.
Failures	Number of frames that were transmitted with an error.

The following table describes the statistics in the DEVICE section of the ifstat command output when you use the command on an FDDI interface.


Statistic	Meaning
Interrupts	Number of times the FDDI device interrupted the host.
Spurious ints	Number of spurious interrupts received from the device.
Resets	Number of times the device was reset due to unrecoverable hardware faults.
Non-existing mem	Number of times the device was asked to address nonexisting memory. This might indicate a software or hardware problem.
Parity errs	Number of parity errors detected on the interface.
Host parity errs	Number of parity errors detected on the host.
Spurious Unsols	Number of unknown unsolicited error events reported by this link entity.
Ring inits in	Number of ring claim processes or ring beacon processes initiated by this link entity.
Ring beacon out	Number of ring beacon processes initiated by this link entity.
Ring beacon in	Number of ring beacon processes recognized by this link entity.
Dupl. address	Number of times the duplicate address test failed.
Dupl. token	Number of times this link entity detected a duplicate token.
Ring purge errs	Number of times the MAC PurgeError Event bit was set.
FCI strip errs	Number of times a Frame Content Independent Strip operation was terminated.
Trace init	Number of PC Traces initiated by this station.
Selftest failures	Number of failed self- tests during device resets.
PC trace rcvd	Number of PC traces received by this station.
Config changes	Number of config changes.
LEM rejects	Number of LEM rejects.
Elastic buf errs	Number of ELM Chip EBUFF_ERROR events.
Link test rejects	Number of link test rejects.

ATM

The following table describes the statistics in the RECEIVE section of the ifstat command output when you use the command on an ATM interface.


Statistic	Meaning
Packets	Number of packets received on the interface.
Bytes	Number of bytes received on the interface.
Errors	Number of errors during Ethernet frame reception, including all kinds of receive errors.
Vpi out of range	Number of packets received on an out-of-range VPI.
Vci out of range	Number of packets received on an out-of-range VCI.
Packets dropped	Number of received packets dropped because of errors reported by the adapter.
No connection	Number of packets received for a disconnected or nonexistent virtual circuit.
Small buffers	Number of small received buffers supplied to the adapter.
Large buffers	Number of large received buffers supplied to the adapter.

The following table describes the statistics in the TRANSMIT section of the ifstat command output when you use the command on an ATM interface.


Statistic	Meaning
Packets	Number of packets attempted to be transmitted.
Bytes	Number of bytes attempted to be transmitted.
Errors	Number of hardware errors encountered while attempting to transmit.
Queue full	Number of packets dropped because they could not be put in the transmit queue.
List full	Number of packets that could not be transmitted because the transmit queue was full.
Iface unavailable	Number of packets that could not be transmitted because the referenced interface was down.

For more information about the ifstat command, see the na_ifstat(1) man page.

Part No. 210-02334
File: stats6.htm
Last updated: 02/24/99 12:17:19