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Quick Tip - SSH Server, Client & Authorized Key Configurations for ESXi 8.0 Update 2 and later

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The general best practice is to disable SSH on your ESXi host by default and if/when you need access, you can turn it on temporarily and disable it when you have completed your task.

For users that need to modify the default SSH configurations whether that is on the server side, client side or setting up SSH authorized keys, this was historically accomplished by manipulating the various SSH configuration files and then reloading the service, if applicable.

With the introduction of the ESXi Configuration Store in vSphere 7.0 Update 1, the process is now different with ESXi 8.0 Update 2 and later for services that requires a configuration file to run such as SSH, NTP or SNMP to name a few.

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Useful NVMe Tiering reporting using vSphere 8.0 Update 3 APIs

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After successfully enabling the NVMe Tiering feature, which was introduced in vSphere 8.0 Update 3, you can find some useful details about your NVMe Tiering configuration by navigating to a specific ESXi host and under Configure->Hardware and under the Memory section as shown in the screenshot below.


There is quite a bit of information that we can see, so lets break down the individual items that are useful from an NVMe Tiering point of view and the specific vSphere APIs that can be used to retrieve this information.

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Quick Tip - Monitoring ESXi remote syslog forwarding

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When an ESXi host is unable to forward its logs to a remote syslog server, a VMkernel Observation (VOB) is automatically raised by the host and it can be used to proactively alert administrators, which has been possible since ESXi 5.0 .... per this blog post from 2012 after some Googling! 😅😂

While I was pretty confident the behavior described above still holds true for our latest ESXi 7.x and 8.x releases, I wanted to be sure before responding back to a colleague. I deployed the latest ESXi 7.0 Update 3q and ESXi 8.0 Update 3b and after configuring syslog forwarding, I disabled the NIC on my Aria Operations for Logs to simulate a network disconnect and I saw the following log entry in /var/log/vobd.log

2024-09-28T21:12:00.298Z: [UserLevelCorrelator] 7452916537us: [esx.problem.vmsyslogd.remote.failure] The host "192.168.30.62:514" has become unreachable. Remote logging to this host has stopped.

By default, ESXi will attempt to retry the remote syslog connection after the configured timeout (default 180 seconds), which is a relatively new configuration option that is available with ESXCLI (esxcli system syslog config set --default-timeout XX).

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