svt-support-capture causing SNMP based monitoring of vSwitch in ESXi to stop working

[KptH]

We have several times (using different simplivity versions up to 4.13) experienced problems with SNMP monitoring of vSwitches after issuing the svt-support-capture in the OVC. After the processing of the command is finished ESXi stops responding correctly to SNMP queries related to vSwitches (SNMP traffic OID, response "no such instance"). Have tried restarting /etc/init.d/snmpd stop -> /etc/init.d/snmpd start without success. Also pls note other SNMP queries not relating to vSwitch works (e.g uptime counter) after svt-support-capture.

A restart of the ESXi host solves the problem but is sometimes quite time-consuming...

Anyone, any ideas?

BR

Kpt. H

[Vinky_99]

@KptH 

Good day!

You may give a try to below ones:

>> Ensure that your SNMP configuration on ESXi hosts is correct. Verify that SNMP is enabled and properly configured on the host, including the community strings and access control.

>> Log Analysis: Examine ESXi logs (e.g., /var/log/vmkernel.log, /var/log/snmpd.log, and /var/log/syslog.log) for any error messages or warnings related to SNMP or network issues. Look for clues that might indicate why SNMP stops working after running the svt-support-capture command.

>> Before and after running the svt-support-capture command, use network capture tools (e.g., Wireshark) to capture SNMP traffic between your SNMP monitoring system and the ESXi host. This can help identify any differences in SNMP packets or responses.

>> Examine the logs generated by the svt-support-capture command for any information or errors related to SNMP or network interfaces. The command might be doing something unexpected to SNMP or network settings.

>> Check the release notes and documentation for your SimpliVity version. There might be known issues or workarounds related to SNMP or the svt-support-capture command.

>> Ensure that you are running the latest available version of SimpliVity. Sometimes, issues like this can be resolved through software updates or patches provided by the vendor.

>> If the issue persists and you cannot find a solution on your own, it's a good idea to open a support case with SimpliVity (now part of HPE). They have access to resources and knowledge specific to their product and can provide guidance or fixes for such issues.

>> Temporary Workaround: As you mentioned, restarting the ESXi host resolves the problem temporarily. While not ideal, you can create a script or automation to detect when SNMP monitoring stops working and automate the host restart process to minimize downtime.

Remember to carefully document all the steps you take and any changes you make to the configuration. This information will be valuable when working with SimpliVity support or when diagnosing the issue further. Additionally, consider testing these changes in a non-production environment before applying them in a production setting to avoid any unexpected disruptions.

I hope this gives some insights.

[Aditya_A]

Hi,

I'd recommend opening a support ticket as log analysis will be required to identify root cause of the issue.
After opening the ticket, you can upload the support capture of one of the SimpliVity nodes and vCenter.

This will be a better route to have this issue addressed for good.

[Aditya_A]

Hi,

Please let me know if you were able to get a case open to address this.