ESXi RAM disk full due to a locked virtual machine log file

Products

• VMware vSphere ESXi

Issue/Introduction

• Unable to power on a virtual machine.
• Unable to register a virtual machine.
• Virtual machine migrations fail.
• The vmkernel.log file (located at /var/log/) contains an entry similar to:
  
  VisorFSRam: 233: Cannot extend visorfs file /var/lib/vmware/hostd/journal/ because its ramdisk (root) is full.
  
• The /tmp/vmware-root directory contains a vmware-vmx-xxx.log file that is large in size.
• The vmware-vmx-xxx.log file (located at /tmp/vmware-root/) cannot be deleted.

Environment

• VMware vSphere ESXi 7.x
• VMware vSphere ESXi 8.x

Cause

This issue occurs because the vmware-vmx-xxx.log file fails to move to the working directory of the virtual machine. This file cannot be deleted because the virtual machine is running and is writing to the file.

Resolution

Identify the virtual machine that is locking the vmware-vmx-xxx.log file, release the lock and delete the log file.

 

To identify the affected virtual machine:

1. Log in to the ESXi host as the root user.
2. Run the command:
   
   grep "Config file:" /tmp/vmware-root/vmware-vmx-xxx.log
   
   Where xxx is the log file number.
   
   You see output similar to:
   
   THH-MM-SS | vmx| Config file: /vmfs/volumes/Datastore/MyVM/MyVM.vmx
   
   
3. To obtain the virtual machine display name, run the command:
   
   grep displayName /vmfs/volumes/Datastore/MyVM/MyVM.vmx
   
   Where /vmfs/volumes/Datastore/MyVM/MyVM.vmx is the virtual machine configuration file path in the step 2 output.
   
   There is a similar output to:
   
   displayName = "MyVM"
   
   Note: The display name of the virtual machine may be different to the configuration file name (for example, if the virtual machine is renamed).

To release the lock on the vmware-vmx-xxx.log file and delete it:

1. Launch vSphere Client.
2. Click the ESXi host in the inventory and click the Virtual Machines tab.
3. Search for the virtual machine display name noted in step 3.
4. To release the lock on the vmware-vmx-xxx.log file, power off the virtual machine.
5. Delete the vmware-vmx-xxx.log file by logging in to the ESXi host and running the command:
   
   rm /tmp/vmware-root/vmware-vmx-xxx.log

Additional Information

For related information, see RAM disk is full (2001550)