cisco 2960 L2(48 port) switch.sudden amber light comes in port(25 -46

[karthikragugb]

I have a cisco L3 3850 catalyst switch connected to 5 stacks of L2 cisco 2960 switches. Suddenly amber light comes in stack 3 and stack 4 switches that too from port 25 to 46 alone in both stacks. That time network disconnects for few seconds and comes back to green.The same configuration has been running for around 4 years but suddenly issue araises now. Kindly help

[Leo Laohoo]

Post the complete output to the following commands: 

1. sh version
2. sh post
3. sh interface status err

pri_core#sh version
Cisco IOS Software [Denali], Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version 16.3.6, RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2018 by Cisco Systems, Inc.
Compiled Wed 28-Feb-18 15:23 by mcpre

Cisco IOS-XE software, Copyright (c) 2005-2018 by cisco Systems, Inc.
All rights reserved. Certain components of Cisco IOS-XE software are
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
with ABSOLUTELY NO WARRANTY. You can redistribute and/or modify such
GPL code under the terms of GPL Version 2.0. For more details, see the
documentation or "License Notice" file accompanying the IOS-XE software,
or the applicable URL provided on the flyer accompanying the IOS-XE
software.

ROM: IOS-XE ROMMON
BOOTLDR: CAT3K_CAA Boot Loader (CAT3K_CAA-HBOOT-M) Version 3.58, RELEASE SOFTWARE (P)

pri_core uptime is 4 years, 28 weeks, 17 hours, 27 minutes
Uptime for this control processor is 4 years, 28 weeks, 17 hours, 30 minutes
System returned to ROM by SSO Switchover
System image file is "flash:packages.conf"
Last reload reason: Power Failure

This product contains cryptographic features and is subject to United
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If you require further assistance please contact us by sending email to
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Technology Package License Information:

-----------------------------------------------------------------
Technology-package Technology-package
Current Type Next reboot
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ipbasek9 Permanent ipbasek9

cisco WS-C3850-24T (MIPS) processor (revision AC0) with 864936K/6147K bytes of memory.
Processor board ID FOC2212L0YB
12 Virtual Ethernet interfaces
56 Gigabit Ethernet interfaces
8 Ten Gigabit Ethernet interfaces
2048K bytes of non-volatile configuration memory.
4194304K bytes of physical memory.
252000K bytes of Crash Files at crashinfo:.
1611414K bytes of Flash at flash:.
0K bytes of at webui:.
252000K bytes of Crash Files at crashinfo-1:.
1611414K bytes of Flash at flash-1:.

Base Ethernet MAC Address : 70:01:b5:99:18:00
Motherboard Assembly Number : 73-16297-05
Motherboard Serial Number : FOC2210744N
Model Revision Number : AC0
Motherboard Revision Number : B0
Model Number : WS-C3850-24T
System Serial Number : FOC2212L0YB

Switch Ports Model SW Version SW Image Mode
------ ----- ----- ---------- ---------- ----
1 32 WS-C3850-24T 16.3.6 CAT3K_CAA-UNIVERSALK9 INSTALL
* 2 32 WS-C3850-24T 16.3.6 CAT3K_CAA-UNIVERSALK9 INSTALL

Switch 01
---------
Switch uptime : 5 hours, 36 minutes

Base Ethernet MAC Address : 70:01:b5:99:10:00
Motherboard Assembly Number : 73-16297-05
Motherboard Serial Number : FOC221074KH
Model Revision Number : AC0
Motherboard Revision Number : B0
Model Number : WS-C3850-24T
System Serial Number : FOC2212L0YA

Configuration register is 0x102

pri_core#sh post
Stored system POST messages:

Switch 1
---------

POST: MBIST Tests : Begin
POST: MBIST Tests : End, Status Passed

POST: CRYPTO Tests : Begin
POST: CRYPTO Tests : End, Status Passed

POST: PHY Loopback: loopback Test : Begin
POST: PHY Loopback: loopback Test : End, Status Passed

POST: Thermal, Temperature Tests : Begin
POST: Thermal, Temperature Tests : End, Status Passed

POST: Thermal, Fan Tests : Begin
POST: Thermal, Fan Tests : End, Status Passed

POST: SIF Tests : Begin
POST: SIF Tests : End, Status Passed

Switch 2
---------

POST: MBIST Tests : Begin
POST: MBIST Tests : End, Status Passed

POST: CRYPTO Tests : Begin
POST: CRYPTO Tests : End, Status Passed

POST: PHY Loopback: loopback Test : Begin
POST: PHY Loopback: loopback Test : End, Status Passed

POST: Thermal, Temperature Tests : Begin
POST: Thermal, Temperature Tests : End, Status Passed

POST: Thermal, Fan Tests : Begin
POST: Thermal, Fan Tests : End, Status Passed

POST: SIF Tests : Begin
POST: SIF Tests : End, Status Passed