Enabling debug mode logging

There's another approach to logging in KVM: configuring debug logging. In the libvirtd configuration file that we just mentioned, there are additional settings you can use to configure this very option. So, if we scroll down to the Logging controls part, these are the settings that we can work with:

• log_level
• log_filters
• log_outputs

Let's explain them step by step. The first option – log_level – describes log verbosity. This option has been deprecated since libvirt version 4.4.0. In the Logging controls section of the file, there's additional documentation hardcoded into the file to make things easier. For this specific option, this is what the documentation says:

Figure 16.1 – Logging controls in libvirtd.conf

What people usually do is see the first part of this output (Logging level description), go to the last line (Iog_level), set it to 1, save, restart the libvirtd service...