EthChnl assert failure on 3850 switch

Question

Any Idea What is this error message all about.  
M2-CCTV-DS(config)#int port-channel 10
int port-channel 10
                 ^
% Invalid input detected at '^' marker.
M2-CCTV-DS(config)#
May 23 13:06:13: EthChnl assert failure: ag == NULL: ../switch/pagp/pagp_switch.c: 1137
May 23 13:06:13: -Traceback= 1#830db5fd318976b0280defe233875463  :10000000+1540BE8 :100000
00+F65FF8 :10000000+F67DA8 :10000000+146C060 :10000000+144D1DC :10000000+156604C :10000000
+1451160 :10000000+D351B0 :10000000+146839C :10000000+27AC29C
May 23 13:06:13: EthChnl assert failure: ag == NULL: ../switch/pagp/pagp_switch.c: 1137
May 23 13:06:13: -Traceback= 1#830db5fd318976b0280defe233875463  :10000000+1540BE8 :100000
00+F65FF8 :10000000+F67DA8 :10000000+146C060 :10000000+144D1DC :10000000+145131C :10000000
+D351B0 :10000000+146839C :10000000+27AC29C
M2-CCTV-DS(config)#
M2-CCTV-DS#sh version
Cisco IOS Software, IOS-XE Software, Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version 03.02.02.SE RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Fri 14-Jun-13 19:24 by prod_rel_team
Cisco IOS-XE software, Copyright (c) 2005-2013 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.
(http://www.gnu.org/licenses/gpl-2.0.html) 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: C3850 Boot Loader (C3850-HBOOT-M) Version 1.1, RELEASE SOFTWARE (P)
 --More--         M2-CCTV-DS uptime is 11 weeks, 4 hours, 23 minutes
Uptime for this control processor is 11 weeks, 4 hours, 25 minutes
System returned to ROM by reload
System restarted at 10:51:15 SG Wed Dec 4 2013
System image file is "flash:packages.conf"
Last reload reason: Reload command
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
[email protected].
 --More--         License Level: Ipbase
License Type: Permanent
Next reload license Level: Ipbase
cisco WS-C3850-24T (MIPS) processor with 4194304K bytes of physical memory.
Processor board ID FOC1739X037
3 Virtual Ethernet interfaces
56 Gigabit Ethernet interfaces
8 Ten Gigabit Ethernet interfaces
2048K bytes of non-volatile configuration memory.
4194304K bytes of physical memory.
250456K bytes of Crash Files at crashinfo:.
1609272K bytes of Flash at flash:.
0K bytes of Dummy USB Flash at usbflash0:.
0K bytes of  at webui:.
250456K bytes of Crash Files at crashinfo-2:.
1609272K bytes of Flash at flash-2:.
0K bytes of Dummy USB Flash at usbflash0-2:.
Base Ethernet MAC Address          : 34:db:fd:a0:23:80
Motherboard Assembly Number        : 73-12238-06
Model Revision Number              : F0
Motherboard Revision Number        : D0
 --More--         Model Number                       : WS-C3850-24T
System Serial Number               : FOC1739X037
Switch Ports Model              SW Version        SW Image              Mode   
     1 32    WS-C3850-24T       03.02.02.SE       cat3k_caa-universalk9 INSTALL
     2 32    WS-C3850-24T       03.02.02.SE       cat3k_caa-universalk9 INSTALL
Switch 02
Switch uptime                      : 7 minutes
Base Ethernet MAC Address          : 50:17:ff:d6:8f:00
Motherboard Assembly Number        : 73-12238-06
Model Revision Number              : F0
Motherboard Revision Number        : D0
Model Number                       : WS-C3850-24T
Configuration register is 0x102

Answer 1

Hi friend,
Our campus core switches (6509) are installed in VSS 1440 architecture. On 'logging console', we get similar messages.
*Jan 16 11:15:00.945: SW1_SP: EthChnl assert failure: swidb2: ../switch/pagp/pagp_switch_util.c: 837
*Jan 16 11:15:00.945: SW1_SP: -Traceback= 416A8CA0 416B5130 416B7020 416B7CAC 416B49B4 416ADCA8 408A2DDC 408A2DC8
*Jan 16 11:15:00.945: SW1_SP: EthChnl assert failure: swidb2: ../switch/pagp/pagp_switch_util.c: 837
*Jan 16 11:15:00.945: SW1_SP: -Traceback= 416A8CA0 416B5130 416B7020 416B7CAC 416B49B4 416ADCA8 408A2DDC 408A2DC8
The IOS Version is 12.2(33)SXI4a  on our VS-S720-10G 5 ports Supervisor Engine 720 10GE. We are running almost latest IOS. The switches are in production now. Any idea on what really causing this message to appear? How can I resolve this? If a software upgrade helps, then what is the best way to upgrade two VSS switches with in a short downtime?
Please assist,
Best regards,