Enabling logging for virtual machines

The console log of a virtual machine can be used for troubleshooting boot issues. The log contains messages only if logging is enabled inside the VM, otherwise the log is empty.

The logging can be turned on by enabling the TTY1 and TTYS0 logging levels in Linux VMs and Emergency Management Services (EMS) console redirection in Windows VMs. You may also enable driver status logging in Windows VMs, to see the list of loaded drivers. This can be useful for troubleshooting a faulty driver or long boot process.

To enable TTY1 and TTYS0 logging in Linux virtual machines

1. Add the line GRUB_CMDLINE_LINUX_DEFAULT="console=tty1 console=ttyS0" to the file /etc/default/grub.

2. Depending on the boot loader, run either

   # grub-mkconfig -o /boot/grub/grub.cfg
   

   or

   # grub2-mkconfig -o /boot/grub2/grub.cfg
   

3. Reboot the VM.

To enable EMS console redirection in Windows virtual machines

1. Start Windows PowerShell by using administrator privileges.

2. In the PowerShell console, set the COM port and baud rate for EMS console redirection. As Windows VMs have only the COM1 port with the transmission rate of 9600 bps, run:

   bcdedit /emssettings EMSPORT:1
   

3. Enable EMS for the current boot entry:

   bcdedit /ems on
   

To enable driver status logging in Windows virtual machines

1. Start System Configuration by using administrator privileges.
2. In the System Configuration windows, open the Boot tab, and select the check boxes OS boot information and Make all boot settings permanent.
3. Confirm the changes and restart the system.