CKEditor 5 itself does not provide server logs. Logs are generated by the backend or service you are using, such as a custom server, CKBox, or CKEditor Cloud Services.
If you are using Cloud Services, logs can be accessed through the Insights Panel, but you first need to enable this feature in the Customer Portal. See Activating Insights feature for instructions. Once enabled, the Insights Panel will let you view business logs. This applies to both SaaS and On-Premises setups. In the On-Premises variant, you can also find logs in the Management Panel.
For On-Premises applications, logs are also available directly from the container’s standard outputs (stdout and stderr). Collaboration Server On-Premises sends logs in JSON format, which means you can store or process them with your preferred logging tools. CKBox On-Premises works in the same way, but it also allows you to enable metric logs by setting the environment variable ENABLE_METRIC_LOGS=true.
More details can be found in the logs and monitoring documentation.