Troubleshooting Tip: FortiGate interface error counters

[mzainuddinahm]

Description

This article describes interface error counters.

Scope

• All FortiGate units.
• The output of the diagnose command may vary depending on the interface driver.

Solution

The counters and their meaning describe what can be seen when using the CLI command:

diagnose hardware deviceinfo nic <interface name>

Rx_Errors = rx error count	The bad frame was marked as an error by PHY.
Rx_CRC_Errors	Frame CRC errors can be caused by several factors. Typically, they are caused by either faulty cabling or as a result of a collision.
Rx_Dropped	Running out of buffer space. A newer error is rx_no_buffer_count.
Rx_Missed_Errors	Equals Rx_FIFO_Errors + CEXTERR (Carrier Extension Error Count). Only valid in 1000M mode, which is marked by PHY.
Tx_Errors=Tx_Aborted_Errors	ECOL, Excessive Collisions Count. Valid in half-duplex mode.
Tx_Window_Errors	LATECOL, Late Collisions Count. Late collisions are collisions that occur after 64-byte time into the transmission of the packet, while working at 10-100 Mb/s data rate, and 512-byte time into the transmission of the packet while working at the 1000 Mb/s data rate. This registers only increments if transmits are enabled and the device is in half-duplex mode.
Tx_Dropped	Number of dropped packets.
Collisions	Total number of collisions experienced by the transmitter. Valid in half-duplex mode.
Rx_Over_Errors	Receive the FIFO overflow event counter.
Rx_Frame_Errors	Same as Rx_Align_Errors. This error is only valid in 10/100M mode.
Tx_Collision_Errors	Errors are experienced when there is a mismatch in duplex settings on both sides of the cable.
Rx_FIFO_Errors	Same as Rx_Missed_Errors; missed packet count.
Tx_Carrier_Errors	The PHY should assert the internal carrier sense signal during every transmission. Failure to do so may indicate that the link has failed, or the PHY has an incorrect link configuration. This register only increments if transmits are enabled. This register is not valid in internal SerDes1 mode (TBI mode for the 82544GC/EI), and is only valid when the Ethernet controller is operating at full duplex.
Rx_Length_Errors	Transmission length error.
Tx_FIFO_Errors	Number of Frame transmission errors due to underflow.
Tx_Heartbeat_Errors	Number of heartbeat errors.
Tx_Single_Collision_Frames	Counts the number of times that a successfully transmitted packet encountered a single collision. The value only increments if transmits are enabled and the Ethernet controller is in half-duplex mode.
Tx_Multiple_Collision_Frames	Multiple Collision Count counts the number of times that a transmitter encountered more than one collision but fewer than 16. The value only increments if transmits are enabled and the Ethernet controller is in half-duplex mode.
Tx_Deferred	Counts defer events. A defer event occurs when the transmitter cannot immediately send a packet due to the medium being busy either because another device is transmitting, the IPG timer has not expired, half-duplex deferral events, reception of XOFF frames, or the link is not up. This register only increments if transmits are enabled. This counter does not increment for streaming transmits that are deferred due to the TX IPG.
Rx_Frame_Too_Longs	Rx frame oversized.
Rx_Frame_Too_Shorts	Rx frames are too short.
Rx_Align_Errors	This error is only valid in 10/100M mode.
Symbol Error Count	SYMERRS - Counts the number of symbol errors between reads. The count increases for every bad symbol received, whether or not a packet is currently being received, and whether or not the link is up. This register only increments in internal SerDes mode.
htx_e_busy	A large volume of HTTP/HTTPs may overload the network processing unit can raise this counter due to the business due to the overload.
htx_drop	Due to the queuing in the network processor, the retransmission can take place and packets can be dropped due to the business or overload of NPU. Therefore the counter may rise if the packets are being dropped continuously.