To capture verbose information about call setup failures, which log level should be enabled?

• A. Info
• B. Debug
• C. Warning
• D. Error

Answer: (B)

When you need to diagnose call setup failures, you want the most detailed visibility into what happens as a call is established. Log levels control how much information the system records. The Debug level provides the finest granularity, capturing the entire trace of events: signaling exchanges, state machine transitions, internal function calls, and exact parameter values with timestamps. This level lets you see exactly where the call setup process goes off track, such as a SIP message being rejected, a timer expiring, or a negotiation step failing, so you can pinpoint the root cause.

In contrast, information-level logs cover general activity but skip the step-by-step trace, while warning and error logs highlight issues without detailing the full sequence that led to them. Debug is the right choice for verbose, actionable insight during troubleshooting. Keep in mind that it generates a lot of data, so enable it briefly and target only the relevant components to avoid performance impact and unnecessary data exposure.