EX3400-48p / 21.4R3-S1.5 / Log Observed: Input/Output control failed for device: /dev/iic0 and offset: 87

Trigger for this issue is unknown.

Logs seen as below on the device in chassisd:

Jun 7 01:00:46 Input/Output control failed for device : /dev/iic0 and offset : 87
Jun 7 01:36:59 Input/Output control failed for device : /dev/iic0 and offset : 87
Jun 7 03:52:54 Input/Output control failed for device : /dev/iic0 and offset : 87
Jun 7 04:57:46 Input/Output control failed for device : /dev/iic0 and offset : 87
Jun 7 06:35:11 Input/Output control failed for device : /dev/iic0 and offset : 87

• There is no service impact due to these logs.
• Issue could be related to cpld version might be old or problematic in case of DCD read failure.
• Issue is in console; DCD read with configuration enabled set system port console log-out-on-disconnect. --> this command hence if on the box where this symptom is seen; may not work as desired.
• Please upgrade latest cpld version 0x6 available

To check the current cpld version; please reach out to TAC.

2026-01-28 : Article Created

2026-08-02: Solution updated.