Cisco 4500X Failover

[FuadG]

Hello everyone,

We experienced a failover last night but I can not understand the sequence of events, especially on which switch the VSL ports went down, did they went down because the switch reloaded for some reason or just by themselves and why fast-hello interfaces become and then lost dual-active capability

Jan 8 00:18:56: %C4K_IOSINTF-5-LMPHWSESSIONSTATE: STANDBY:Lmp HW session DOWN on slot 1 port 1.
Jan 8 00:18:56: %FASTHELLO-5-FH_DUAL_ACTIVE_CAP: STANDBY: Fast-Hello interface Te1/1/1 became dual-active detection capable

Jan 8 00:28:12: %SFF8472-5-THRESHOLD_VIOLATION: STANDBY:Te1/1/6: Rx power low alarm; Operating value: -40.0 dBm, Threshold value: -13.9 dBm.
Jan 8 00:38:12: %SFF8472-5-THRESHOLD_VIOLATION: STANDBY:Te1/1/6: Rx power low alarm; Operating value: -40.0 dBm, Threshold value: -13.9 dBm.
Jan 8 00:42:46: %C4K_IOSINTF-5-LMPHWSESSIONSTATE: STANDBY:Lmp HW session DOWN on slot 1 port 1.
Jan 8 00:42:46: %FASTHELLO-5-FH_DUAL_ACTIVE_CAP: STANDBY: Fast-Hello interface Te1/1/1 became dual-active detection capable

Jan 8 00:42:54: %C4K_IOSINTF-5-LMPHWSESSIONSTATE: STANDBY:Lmp HW session DOWN on slot 1 port 1.
Jan 8 00:42:55: %FASTHELLO-5-FH_DUAL_ACTIVE_CAP: STANDBY: Fast-Hello interface Te1/1/1 became dual-active detection capable

Jan 8 02:34:16: %VSLP-3-VSLP_LMP_FAIL_REASON: STANDBY:Te1/1/16: Link down
Jan 8 02:34:16: %VSLP-3-VSLP_LMP_FAIL_REASON: STANDBY:Te1/1/15: Link down
Jan 8 02:34:16: %VSLP-2-VSL_DOWN: STANDBY: All VSL links went down while switch is in Standby role

Jan 8 02:34:16: %EC-5-UNBUNDLE: STANDBY:Interface TenGigabitEthernet1/1/15 left the port-channel Port-channel10
Jan 8 02:34:16: %EC-5-UNBUNDLE: STANDBY:Interface TenGigabitEthernet1/1/16 left the port-channel Port-channel10
Jan 8 02:34:16: %C4K_REDUNDANCY-6-INIT: Initializing as ACTIVE supervisor
Jan 8 02:34:16: %C4K_REDUNDANCY-3-COMMUNICATION: Communication with the peer Supervisor has been lost
Jan 8 02:34:16: %C4K_REDUNDANCY-3-SIMPLEX_MODE: The peer Supervisor has been lost
Jan 8 02:34:16: %FASTHELLO-2-FH_DOWN: Fast-Hello interface Te2/1/1 lost dual-active detection capability

Jan 8 02:34:17: %C4K_IOSINTF-5-LMPHWSESSIONSTATE: Lmp HW session DOWN on slot 1 port 1.

Jan 8 02:34:18: %FASTHELLO-2-FH_DOWN: Fast-Hello interface Te1/1/1 lost dual-active detection capability

Jan 8 02:34:19: %EC-5-UNBUNDLE: Interface Te2/1/6 left the port-channel Po40
Jan 8 02:34:19: %EC-5-UNBUNDLE: Interface Te2/1/7 left the port-channel Po40
Jan 8 02:34:19: %EC-5-UNBUNDLE: Interface TenGigabitEthernet2/1/15 left the port-channel Port-channel20
Jan 8 02:34:19: %EC-5-UNBUNDLE: Interface TenGigabitEthernet2/1/16 left the port-channel Port-channel20

Jan 8 02:35:25: %C4K_L2MAN-6-INVALIDSOURCEADDRESSPACKET: Packet received with invalid source MAC address (00:00:00:00:00:00) on port Te1/1/4 in vlan 828
Jan 8 02:38:13: %SFF8472-5-THRESHOLD_VIOLATION: Te1/1/6: Rx power low alarm; Operating value: -40.0 dBm, Threshold value: -13.9 dBm.
Jan 8 02:40:57: %C4K_IOSINTF-5-LMPHWSESSIONSTATE: Lmp HW session UP on slot 1 port 15.
Jan 8 02:40:59: %C4K_IOSINTF-5-LMPHWSESSIONSTATE: Lmp HW session UP on slot 1 port 16.
Jan 8 02:41:13: %VSLP-5-VSL_UP: Ready for control traffic

Jan 8 02:41:17: %VSLP-5-RRP_ROLE_RESOLVED: Role resolved as ACTIVE by VSLP
Jan 8 02:41:17: %EC-5-BUNDLE: Interface TenGigabitEthernet1/1/15 joined port-channel Port-channel10
Jan 8 02:41:17: %EC-5-BUNDLE: Interface TenGigabitEthernet1/1/16 joined port-channel Port-channel10
Jan 8 02:41:18: %C4K_REDUNDANCY-6-DUPLEX_MODE: The peer Supervisor has been detected
Jan 8 02:42:00: %C4K_REDUNDANCY-6-MODE: ACTIVE supervisor initializing for sso mode
Jan 8 02:42:01: %C4K_REDUNDANCY-3-COMMUNICATION: Communication with the peer Supervisor has been established
Jan 8 02:42:19: %C4K_REDUNDANCY-5-CONFIGSYNC: The bootvar has been successfully synchronized to the standby supervisor
Jan 8 02:42:19: %C4K_REDUNDANCY-5-CONFIGSYNC: The config-reg has been successfully synchronized to the standby supervisor
Jan 8 02:42:19: %C4K_REDUNDANCY-5-CALENDAR: The calendar has been successfully synchronized to the standby supervisor for the first time
Jan 8 02:42:19: %C4K_REDUNDANCY-5-CONFIGSYNC: The startup-config has been successfully synchronized to the standby supervisor
Jan 8 02:42:20: %C4K_REDUNDANCY-5-CONFIGSYNC: The private-config has been successfully synchronized to the standby supervisor
Jan 8 02:42:21: %C4K_REDUNDANCY-5-CONFIGSYNC_RATELIMIT: The vlan database has been successfully synchronized to the standby supervisor
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=2: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=3: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=4: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=6: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=7: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=12: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=15: Transceiver has been inserted
Jan 8 02:42:22: %C4K_IOSINTF-5-TRANSCEIVERINSERTED: Slot=11 Port=16: Transceiver has been inserted
Jan 8 02:43:19: %EC-5-BUNDLE: Interface TenGigabitEthernet2/1/15 joined port-channel Port-channel20
Jan 8 02:43:19: %EC-5-BUNDLE: Interface TenGigabitEthernet2/1/16 joined port-channel Port-channel20
Jan 8 02:43:23: %HA_CONFIG_SYNC-6-BULK_CFGSYNC_SUCCEED: Bulk Sync succeeded
Jan 8 02:43:24: %RF-5-RF_TERMINAL_STATE: 1 ha_mgr: Terminal state reached for (SSO)
Jan 8 02:43:25: %FASTHELLO-5-FH_UP: Fast-Hello interface Te1/1/1 status changed to link up

Jan 8 02:43:25: %FASTHELLO-5-FH_UP: Fast-Hello interface Te2/1/1 status changed to link up

Jan 8 02:43:22: %C4K_IOSMODPORTMAN-6-MODULEONLINE: STANDBY:Module 1 (WS-C4500X-16 S/N: JAE20030D4A Hw: 1.1) is online
Jan 8 02:43:22: %C4K_IOSMODPORTMAN-6-MODULEONLINE: STANDBY:Module 11 (WS-C4500X-16 S/N: JAE20030AUT Hw: 1.1) is online
Jan 8 02:43:23: %FASTHELLO-5-FH_UP: STANDBY: Fast-Hello interface Te2/1/1 status changed to link up
Jan 8 02:43:23: %FASTHELLO-5-FH_UP: STANDBY: Fast-Hello interface Te1/1/1 status changed to link up
Jan 8 02:43:26: %FASTHELLO-5-FH_DUAL_ACTIVE_CAP: Fast-Hello interface Te1/1/1 became dual-active detection capable

Jan 8 02:43:25: %FASTHELLO-5-FH_DUAL_ACTIVE_CAP: STANDBY: Fast-Hello interface Te2/1/1 became dual-active

[marce1000]

                 >...the switch reloaded for some reason 
 - Check current software version and upgrade to the latest (advisory) , check if that can help.

 M.

[FuadG]

Hello Marce,

We will definitely consider this option but meanwhile can you pls assist in understanding what happened? 

[marce1000]

  - Probably a bug/crash , hence the reload and also my advice ; look for crashinfo directory on the devices and crash files (e.g.) ; and or use the command show version and look for the reload reason(s) in the output of that command.
   Also  configure a central syslog server on the 4500's and follow up on logs send to it on the future (for monitoring and better understanding of future events)

 M.

[Leo Laohoo]

Post the complete output to the following commands: 

sh version
dir crashinfo:
dir slavecrashinfo:
sh log on uptime detail

[FuadG]

Hello Leo,

sh version:

Cisco IOS Software, IOS-XE Software, Catalyst 4500 L3 Switch Software (cat4500e-UNIVERSALK9-M), Version 03.06.03.E RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2015 by Cisco Systems, Inc.
Compiled Wed 26-Aug-15 06:05 by prod_rel_team

Cisco IOS-XE software, Copyright (c) 2005-2015 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: 15.0(1r)SG11
BCT-VSS-01 uptime is 7 years, 5 weeks, 2 days, 27 minutes
Uptime for this control processor is 4 days, 8 hours, 53 minutes
System returned to ROM by SSO Switchover
System restarted at 04:11:30 az Sat Jan 13 2024
Running default software
Jawa Revision 2, Winter Revision 0x0.0x41

Last reload reason: Critical software exception

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
export@cisco.com.

License Information for 'WS-C4500X-16'
License Level: entservices Type: Permanent Right-To-Use
Next reboot license Level: entservices

cisco WS-C4500X-16 (MPC8572) processor (revision 9) with 4194304K bytes of physical memory.
Processor board ID JAE20030D4A
MPC8572 CPU at 1.5GHz, Cisco Catalyst 4500X
Last reset from Reload
54 Virtual Ethernet interfaces
32 Ten Gigabit Ethernet interfaces
511K bytes of non-volatile configuration memory.

Configuration register is 0x2101

dir crashinfo:

Directory of crashinfo:/

62498 -rw- 0 Jan 13 2024 04:10:05 +04:00 cilogs
62499 -rw- 0 Jan 29 2016 05:27:17 +04:00 koops.dat
62500 -rw- 960 Jan 13 2024 04:07:31 +04:00 deleted_crash_files
62501 -rwx 3952751 Jan 13 2024 04:07:31 +04:00 crashinfo_iosd_20240113-000600-UTC
62502 -rw- 44 Jan 13 2024 04:07:31 +04:00 last_crashinfo
62507 -rwx 67524364 Jan 13 2024 04:07:32 +04:00 fullcore_iosd_20240113-000600-UTC
62503 -rwx 3932972 Feb 18 2023 21:37:16 +04:00 crashinfo_iosd_20230218-173545-UTC
62504 -rwx 67396799 Feb 18 2023 21:37:17 +04:00 fullcore_iosd_20230218-173545-UTC
62505 -rwx 3935054 Dec 26 2023 09:06:58 +04:00 crashinfo_iosd_20231226-050528-UTC
62506 -rwx 68028176 Dec 26 2023 09:06:59 +04:00 fullcore_iosd_20231226-050528-UTC

278754304 bytes total (61001728 bytes free)

dir slavecrashinfo:

Directory of slavecrashinfo:/

58466 -rw- 0 Jan 16 2024 19:01:04 +04:00 cilogs
58467 -rw- 0 Jan 29 2016 05:27:05 +04:00 koops.dat
58468 -rw- 704 Jan 16 2024 18:58:39 +04:00 deleted_crash_files
58469 -rwx 3907735 Jan 8 2024 02:35:48 +04:00 crashinfo_iosd_20240107-223418-UTC
58470 -rw- 44 Jan 16 2024 18:58:40 +04:00 last_crashinfo
58471 -rwx 67554776 Jan 8 2024 02:35:49 +04:00 fullcore_iosd_20240107-223418-UTC
58472 -rwx 3899155 Jan 16 2024 18:58:39 +04:00 crashinfo_iosd_20240116-145710-UTC
58473 -rwx 67307872 Jan 16 2024 18:58:40 +04:00 fullcore_iosd_20240116-145710-UTC
58474 -rwx 3925571 Dec 3 2023 05:28:02 +04:00 crashinfo_iosd_20231203-012631-UTC
58475 -rwx 68346749 Dec 3 2023 05:28:03 +04:00 fullcore_iosd_20231203-012631-UTC

278754304 bytes total (60832768 bytes free)

sh log on uptime detail

Executing the command on VSS member switch role = VSS Active, id = 1

--------------------------------------------------------------------------------
UPTIME SUMMARY INFORMATION
--------------------------------------------------------------------------------
First customer power on : 01/17/2016 21:09:20
Total uptime : 7 years 44 weeks 1 days 1 hours 15 minutes
Total downtime : 0 years 8 weeks 1 days 21 hours 16 minutes
Number of resets : 47
Number of slot changes : 1
Current reset reason : 0x9
Current reset timestamp : 01/13/2024 04:14:54
Current slot : 1
Current subslot : 0
Current uptime : 0 years 0 weeks 4 days 8 hours 0 minutes
--------------------------------------------------------------------------------
Reset | |
Reason | Count |
--------------------------------------------------------------------------------
No historical data to display
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
UPTIME CONTINUOUS INFORMATION
--------------------------------------------------------------------------------
Time Stamp | Reset | Uptime
MM/DD/YYYY HH:MM:SS | Reason | years weeks days hours minutes
--------------------------------------------------------------------------------
01/17/2016 21:09:20 0x0 0 0 0 0 0
01/17/2016 21:17:24 0x0 0 0 0 0 0
01/29/2016 05:29:46 0x0 0 0 0 0 20
01/29/2016 05:47:40 0x9 0 0 0 0 5
01/29/2016 06:12:26 0x0 0 0 0 0 0
01/29/2016 06:28:40 0x0 0 0 0 0 0
03/14/2016 01:40:38 0x0 0 0 0 0 0
03/14/2016 02:37:53 0x0 0 0 0 0 10
03/14/2016 07:09:13 0x9 0 0 0 4 0
03/28/2016 07:00:53 0x0 0 1 6 23 0
05/01/2016 23:17:49 0x0 0 4 6 16 0
05/24/2016 07:29:57 0x0 0 3 1 8 0
05/24/2016 08:23:13 0x9 0 0 0 0 40
05/25/2016 06:34:31 0x9 0 0 0 22 0
05/25/2016 06:57:26 0x9 0 0 0 0 15
05/25/2016 09:27:09 0x9 0 0 0 2 0
10/10/2016 08:42:09 0x0 0 19 4 23 0
10/10/2016 09:13:12 0x0 0 0 0 0 15
10/11/2016 04:05:39 0x9 0 0 0 18 0
10/11/2016 04:18:44 0x9 0 0 0 0 5
10/11/2016 04:55:26 0x9 0 0 0 0 30
10/11/2016 16:20:50 0x0 0 0 0 3 0
10/13/2016 08:55:20 0x0 0 0 2 0 0
10/13/2016 18:40:32 0x0 0 0 0 1 0
10/13/2016 18:56:50 0x9 0 0 0 0 5
12/12/2016 12:31:20 0x9 0 8 3 17 0
12/17/2016 13:02:32 0x9 0 0 5 0 0
05/27/2017 16:32:00 0x9 0 23 0 3 0
07/13/2017 10:06:01 0x9 0 6 4 17 0
08/31/2017 03:21:33 0x0 0 6 6 16 0
12/12/2017 22:50:57 0x0 0 14 5 19 0
07/03/2018 00:30:56 0x0 0 28 6 1 0
07/03/2018 03:04:14 0x0 0 0 0 0 10
07/03/2018 03:41:33 0x0 0 0 0 0 30
07/03/2018 04:41:59 0x0 0 0 0 0 10
07/03/2018 19:50:23 0x0 0 0 0 14 0
07/20/2018 22:57:32 0x0 0 2 3 2 0
01/27/2019 13:09:27 0x0 0 27 1 13 0
04/07/2019 09:10:50 0x0 0 9 6 19 0
02/13/2021 21:36:09 0x9 1 44 5 12 0
02/23/2022 08:25:50 0x9 1 1 2 10 0
10/25/2022 08:24:35 0x9 0 34 5 23 0
02/14/2023 12:58:47 0x9 0 16 0 4 0
02/16/2023 20:43:33 0x9 0 0 2 7 0
02/18/2023 21:44:17 0x9 0 0 2 0 0
12/26/2023 09:14:21 0x9 0 44 2 11 0
01/13/2024 04:14:54 0x9 0 2 3 18 0
--------------------------------------------------------------------------------

Executing the command on VSS member switch role = VSS Standby, id = 2

--------------------------------------------------------------------------------
UPTIME SUMMARY INFORMATION
--------------------------------------------------------------------------------
First customer power on : 01/17/2016 21:09:17
Total uptime : 7 years 44 weeks 1 days 1 hours 25 minutes
Total downtime : 0 years 8 weeks 1 days 13 hours 31 minutes
Number of resets : 46
Number of slot changes : 2
Current reset reason : 0x9
Current reset timestamp : 01/16/2024 19:05:34
Current slot : 11
Current subslot : 0
Current uptime : 0 years 0 weeks 0 days 17 hours 0 minutes
--------------------------------------------------------------------------------
Reset | |
Reason | Count |
--------------------------------------------------------------------------------
No historical data to display
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
UPTIME CONTINUOUS INFORMATION
--------------------------------------------------------------------------------
Time Stamp | Reset | Uptime
MM/DD/YYYY HH:MM:SS | Reason | years weeks days hours minutes
--------------------------------------------------------------------------------
01/17/2016 21:09:17 0x0 0 0 0 0 0
01/17/2016 21:17:21 0x0 0 0 0 0 0
01/29/2016 05:29:35 0x0 0 0 0 0 20
01/29/2016 05:48:35 0x9 0 0 0 0 5
01/29/2016 06:13:16 0x0 0 0 0 0 0
01/29/2016 06:29:33 0x0 0 0 0 0 0
03/14/2016 04:21:39 0x0 0 0 0 0 0
03/14/2016 04:55:21 0x0 0 0 0 0 20
03/14/2016 07:10:09 0x9 0 0 0 2 0
03/28/2016 07:46:46 0x0 0 1 6 23 0
05/24/2016 07:28:38 0x9 0 8 0 23 0
05/24/2016 08:15:45 0x9 0 0 0 0 20
05/25/2016 02:21:35 0x9 0 0 0 17 0
05/25/2016 05:47:56 0x9 0 0 0 0 30
05/25/2016 05:58:39 0x0 0 0 0 0 0
05/25/2016 06:17:10 0x0 0 0 0 0 5
05/25/2016 06:44:05 0x9 0 0 0 0 15
05/25/2016 07:27:06 0x0 0 0 0 0 20
05/25/2016 07:51:37 0x9 0 0 0 0 15
05/25/2016 08:04:22 0x9 0 0 0 0 5
05/25/2016 08:16:08 0x9 0 0 0 0 5
05/25/2016 08:47:05 0x9 0 0 0 0 20
05/25/2016 09:28:04 0x9 0 0 0 0 30
10/10/2016 08:42:58 0x0 0 19 4 23 0
10/10/2016 09:36:03 0x0 0 0 0 0 15
10/10/2016 09:50:59 0x0 0 0 0 0 5
10/10/2016 10:06:20 0x9 0 0 0 0 5
10/11/2016 04:06:30 0x9 0 0 0 17 0
10/13/2016 08:56:14 0x0 0 0 2 4 0
10/13/2016 18:20:26 0x9 0 0 0 1 0
10/13/2016 18:48:21 0x9 0 0 0 0 20
10/13/2016 19:09:10 0x9 0 0 0 0 10
12/12/2016 12:32:11 0x9 0 8 3 17 0
12/17/2016 14:27:23 0x9 0 0 5 1 0
07/12/2017 19:32:58 0x9 0 29 4 4 0
07/12/2017 19:43:46 0x9 0 0 0 0 0
05/03/2019 21:44:07 0x9 1 42 1 1 0
03/06/2021 11:49:41 0x0 1 43 6 13 0
03/06/2021 11:58:59 0x0 0 0 0 0 0
09/30/2022 04:05:58 0x9 1 29 4 15 0
02/13/2023 06:07:21 0x9 0 19 3 1 0
02/16/2023 19:20:30 0x9 0 0 3 13 0
02/18/2023 13:11:47 0x9 0 0 1 17 0
12/03/2023 05:34:54 0x9 0 41 0 16 0
01/08/2024 02:43:13 0x9 0 5 0 20 0
01/16/2024 19:05:34 0x9 0 1 1 16 0
--------------------------------------------------------------------------------

I can see reload reason as Last reload reason: Critical software exception

I wonder which critical exception it is since we had one issue before with this VSS when some kind of DHCP packets were causing an exception and once we figured our which interface vlan was causing it and shut it down, all returned to normal

https://community.cisco.com/t5/switching/4500x-vss-unexpected-reload-of-both-switches/td-p/4776954

[Leo Laohoo]

---

@FuadG wrote:

62501 -rwx 3952751 Jan 13 2024 04:07:31 +04:00 crashinfo_iosd_20240113-000600-UTC
58469 -rwx 3907735 Jan  8 2024 02:35:48 +04:00 crashinfo_iosd_20240107-223418-UTC​

 

---

I want to see those two files.  

For obvious reasons, chassis 2 crashed first and then chassis 1 crashed a few days later.

[FuadG]

Hello Leo,

Files attached. Once thing to mention - we had a reload yesterday, Jan 16 as well

[marce1000]

            >...Files attached. Once thing to mention - we had a reload yesterday, Jan 16 as well
 - Check current software version being used , upgrade to an advisory release , if applicable and check if that can help , 

 M.

[FuadG]

Hello @marce1000 

VSS upgrade is a tricky thing and I would like to know the root cause of the problem first before choosing to which version I should upgrade

[marce1000]

  >...VSS upgrade is a tricky thing and I would like to know the root cause of the problem first before choosing to which version I should upgrade
  - To be honest ; the first line of the crashinfo file : Signal 11 , is already a very strong indicator for a bug , hence upgrading (to the latest advisory) remains strongly advised and will probably  be 'the single possible path forward'

 M.

[Leo Laohoo]

---

@FuadG wrote:

IOSD-EXT-SIGNAL: Segmentation fault(11), Process = DHCPD Receive​

---

This VSS has crashed before on 13 and 16 February 2023.  

Cause of the crash is the same thing and you have posted a thread about it:  4500X VSS Unexpected reload of both switches

Here are the options:

1.  Disable DHCP
2.  Upgrade the firmware
3.  Get used to it

[FuadG]

Hello Leo,

Yes, 13th and 16th is clear. What about the recent crash? Is it the same cause?

[Leo Laohoo · Accepted solution]

Same cause.  Same issue.  Same bug.