Step-by-Step Explanation of Ballooning, Compression & Swapping in VMware

 VMware Q & Answer 

10. Host is reporting “All Paths Down” (APD) error. How would you troubleshoot?

Check the storage array’s connectivity and health.

Verify that the storage devices are properly connected and multipath settings are correct.

Restart the management agents on the ESXi host and check logs to identify specific path issues.

11. You receive alarms for memory ballooning on a host. What would you do?

Check the host’s memory usage and VM allocations.

Reduce memory reservation or ballooning for specific VMs, or add more physical memory if possible.

Enable transparent page sharing (TPS) or review the need for vSwap.

12. The ESXi host goes into a “Not Responding” state in vCenter. How do you resolve it?

Check network connectivity between vCenter and the ESXi host.

SSH into the host to restart management agents (/etc/init.d/hostd restart and /etc/init.d/vpxa restart).

If the host is still down, reboot it after ensuring VMs are unaffected.

13. You need to troubleshoot latency issues on a VM’s network. What steps would you follow?

Check the VM’s network adapter settings and the host’s NIC settings.

Review the switch port for any configuration issues.

Use tools like esxtop to check for network performance bottlenecks.

Verify vDS or standard switch configurations, such as load balancing and NIC teaming.

14. How would you handle a situation where vCenter Server Appliance (VCSA) root partition is full?

SSH into the VCSA and check disk usage (df -h).

Identify and clean up unnecessary logs or files in /var/log or /storage/log.

Adjust the log rotation settings to prevent this issue in the future.

15. A VM shows “Inaccessible” in vCenter. What are your next steps?

Check if the datastore hosting the VM is connected and available.

Rescan datastores on the host or re-add the datastore if it has become disconnected.

If the VM files are missing or corrupt, restore from backup if necessary.