What is VMware log file?

VMware creates log files to record various types of information, errors, warnings, and other events that occur in the VMware environment. These log files play a crucial role in monitoring, troubleshooting, and debugging issues with VMware products like vSphere, ESXi hosts, vCenter Server, and more.

What is VMware log file?

Types of VMware Log Files

There are various types of log files generated by different VMware products and components:

vSphere and ESXi Host Logs

These include:

  • vmkernel.log: Captures kernel events and activities.
  • vmkwarnings.log: Stores kernel warnings.
  • vpxa.log: Logs vSphere Client and vCenter Server activities.
  • hostd.log: Records events related to host agents/services.

vCenter Server Logs

Important vCenter Server logs include:

  • vpxd.log: Key vCenter Server service activities.
  • inventoryService.log: Logs inventory events.
  • Mbcs.log: Events of vCenter Server message bus communication.

Virtual Machine Logs

The key virtual machine log files are:

  • vmware.log: Broad range of VM activities.
  • vmkwarnings.log: Lists virtual machine warnings.

There are also logs for specific VMware services like Update Manager, Auto Deploy, Horizon, NSX, vSAN and so on.

Common Log File Locations

The default locations for main VMware log files are:

  • ESXi Hosts – /var/log/ directory
  • vCenter Server (VCSA) – /var/log/vmware/ directory

The logs are located in appropriate sub-directories like vpxa/, hostd/ etc.

For virtual machines, the logs are found under VM home directory:

  • C:\ProgramData\VMware\vmdata (Windows VMs)
  • /vmfs/volumes (Linux VMs)

It’s possible to customize log locations as needed.

Key Uses and Importance

Some main uses and significance of VMware logs include:

Performance Monitoring – Track resource consumption, bottlenecks.

Troubleshooting Issues – Diagnose and fix problems faster.

Security Audits – Review activities for anomalies.

Forensic Investigations – Reconstruct sequence of events after an incident.

Compliance – Validate adherence to standards.

Careful log analysis provides deeper visibility into VMware environments.

Best Practices for Managing Logs

Here are some vital best practices for effective administration of VMware logs:

  • Collect Logs Centrally – Use log insight/analytics tools to gather logs from all sources.
  • Set Proper Log Rotation – Avoid uncontrolled log growth and storage crunch.
  • Monitor Logs Proactively – Review frequently, set alerts for faster problem detection.
  • Control Log Levels – Adjust verbosity as needed while avoiding large debug logs in production.
  • Secure Logs – Prevent unauthorized access to safeguard sensitive data.
  • Retain Logs – Maintain archived logs for future requirements like audits or forensics.

The key is striking a balance between log visibility and available resources.

Key Takeaway

  • VMware log files provide visibility into activities, issues, and events across the VMware stack including vSphere, ESXi, vCenter Server and VMs.
  • Main logs to monitor include vmkernel.log, vpxa.log, vpxd.log and vmware.log.
  • Managing logs via centralized collection, proper rotation, proactive monitoring, and secure retention is vital.
  • Careful log analysis delivers deeper troubleshooting insight and can aid security/compliance.


In conclusion, VMware generates extensive logs across its products that record countless events, warnings, errors and operations. Mastering these logs by harvesting them centrally and mining them for insights using analytics is key for optimal visibility and management. Log monitoring and retention helps keep VMware environments running smoothly, securely and in compliance. The time invested in crafting a sound logging strategy pays rich dividends over the long run.

Frequently Asked Questions (FAQs) Based on Search Queries

Q1: Where are VMware logs stored?
VMware stores logs in directories like /var/log/ on ESXi hosts and /var/log/vmware/ on vCenter Server. Virtual Machine logs are stored in locations like C:\ProgramData\VMware\vmdata on Windows VMs.

Q2: How do I collect VMware logs?
Use tools like vRealize Log Insight or vCenter Server to centrally aggregate logs from all VMware components. Also configure syslog servers to gather logs.

Q3: What is vmkernel.log?
vmkernel.log is the key ESXi host log that records kernel events, memory stats, storage adapter info, driver activities and other vmkernel data.

Q4: How long should VMware logs be kept?
Best practice is retaining VMware logs for 6-12 months for troubleshooting, security and compliance needs before archiving. Critical logs may be retained longer as per regulatory policies.

Q5: What VMware log level should I set?
In production avoid verbose, debug logs. INFO/WARNING provides a balance for troubleshooting without excessive logs. Further adjust based on monitoring needs.

Q6: What is verbose logging in VMware?
Verbose logging captures detailed low-level debug information from VMware components. Avoid in production due to high resource usage but can help diagnosing complex issues.

Q7: Where are VMware ESXi host logs stored?
ESXi host log files are stored in the /var/log/ directory by default including logs like vmkernel.log, vobd.log, vpxa.log and hostd.log files.

Q8: How do I view VMware ESXi host logs?
Use SSH to login to the ESXi host and view logs in /var/log/ or use the esxtop tool. vCenter also allows viewing ESXi logs under the Monitor tab or via scripted methods.

Q9: What is the vpxd.log file?
vpxd.log records key events, activities and errors related to the vCenter Server service which coordinates vCenter operations and allows managing vSphere infrastructure.

Q10: How do I increase VMware log size?
Edit /etc/vmware/hostd/config.xml on ESXi or /etc/vmware-syslog/vmware-syslog.conf on vCenter Server to set higher log size limits. Also adjust log rotation settings.

Q11: What is Scratch partition in VMware?
Scratch partitions temporarily store VMware log files before they are rotated to final log locations. Aids log management but should be monitored for disk usage.

Q12: Where are vCenter Server appliance logs?
vCenter Server appliance (VCSA) default log location is /var/log/vmware/ directory and subdirectories. Also accessible remotely via VAMI/vSphere interfaces.

Q13: What port does VMware use for logging?
By default VMware uses UDP port 514 for syslog logging and port 1514 for encrypted TLS syslog output directed to remote log servers.

Q14: What time is used in VMware logs?
VMware log timestamps use UTC/GMT timezone by default. This can be changed to local timezone either globally (via vCenter settings) or per ESXi host using CLI.

Q15: Where is VMware.log located on Windows?
For Windows VMs, default location for vmware.log is C:\ProgramData\VMware\VMware Virtual Infrastructure Logs folder. Configurable during VM creation.

Q16: How do I analyze VMware log files?
Use log analytics programs like vRealize Log Insight, vCenter Log Browser or third party log management tools that provide dashboards/visualization to gain insights from VMware logs.

Q17: Why is my vmware.log so big?
Large vmware logs are often due to verbose logging enabled mistakenly or log rotation issues. Adjust log levels to INFO and restrict size/period for log rotation via .vmx file settings.

Q18: How do I log into vCenter appliance?
Use ssh to login to vCenter Server appliance IP on default port 22 to access logs under /var/log/vmware directory. Or login remotely via VMware Host Client interface.

Q19: What is scrlogd in VMware?
scrlogd is ESXi system daemon responsible for rotating hostd, vpxa and xorg logs from temporary scratch logs to final log destinations based on rotation policies.

Q20: How do I troubleshoot VMware installation problems?
Examine main installation logs under /var/log/vmware/ like vcsa-deploy.log while troubleshooting VMware deploy issues and correlate timestamped errors across components.

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