Error symbol and Illegal symbol count incrementing on a NIC port

Applies to

• FAS, AFF
• Network port
• ONTAP 9.2 or higher.

Issue

• CRC errors reported in EMS messages. Example:

[node_name: vifmgr: vifmgr.cluscheck.crcerrors:alert]: Port e0g on node node_name is reporting a high number of observed hardware errors, possibly CRC errors.
 

• Increasing Error and/or Illegal symbol count observed in ifstat -a output of that NIC port, along with CRC errors. Example:

::> system node run -node <node_name> -command ifstat <port_name>
    -- interface  e0g  (123 days, 4 hours, 5 minutes, 6 seconds) --
    RECEIVE
    Total frames:      117g | Frames/second:    1798  | Total bytes:       175t
    Bytes/second:     2680k | Total errors:     1538k | Errors/minute:       1
     Total discards:      0  | Discards/minute:     0  | Multi/broadcast: 31222k
    Non-primary u/c:     0  | CRC errors:       1522k | Runt frames:         0
     Fragment:         1107  | Long frames:         0  | Jabber:              0
     Length errors:      96  | No buffer:           0  | Xon:                 0
     Xoff:                0  | Pause:               0  | Jumbo:               0
     Noproto:             0  | Error symbol:     1234  | Illegal symbol:    5678
    ...