So do you have a large and complex Oracle Exadata environment and need to perform a health check or resolve a tricky issue? Well, one thing to keep in mind is that Oracle support may ask you to run some diagnostics to provide logs and so forth. This is where the utility exachk comes to the resue!
What is exachk? Well according to the Oracle Exadata documentation, this nifty utility "provide a lightweight and non-intrusive health check framework for the Oracle stack of software and hardware components."
As an extra bonus, the ExaChk utility works not only for Oracle Exadata engineered systems, but can diagnose issues with other Oracle database appliances such as the Exalogic and Oracle Database Appliance (ODA) systems. Recently, we had a power issue at work that required me to troubleshoot why the Oracle Clusterware (CRS) and ASM failed to come back on line after the power reboot. I tried to start the CRS using standard Oracle 19c RAC commands like crsctl and srvctl with no success as it complained about storage related issues on the Exadata Cloud @ Customer environment since we DBAs unfortunately are not provided with access to the grid disks and cell storage servers due to the setup. So how do you use Exachk? It is really simple actually. You can run it by default as the grid user and by default it runs all of the options to perform a full collection of the Exadata ecosystem. If you use the exachk -a that will run all options for diagnostic collection tasks. It then collects the details for the health check of the Exadata system into a series of tar files to upload to Oracle support.
So the next time you face a challenging Exadata or Oracle engineered system issue, be sure to use the powerful ExaChk utility!
References and Further Reading
Oracle Exadata Database Machine EXAchk (Doc ID 1070954.1)
Oracle Exachk Quick Start Guide
https://docs.oracle.com/en/engineered-systems/health-diagnostics/exachk/oexug/quick-start-guide.html#GUID-7C8BEBDC-5125-4493-A8FC-799023FAFC06