AppInsightsTelemetryInitializer.cs

using Microsoft.ApplicationInsights.Channel;
using Microsoft.ApplicationInsights.Extensibility;

namespace TasksTracker.Processor.Backend.Svc
{
    public class AppInsightsTelemetryInitializer : ITelemetryInitializer
    {
        public void Initialize(ITelemetry telemetry)
        {
            if (string.IsNullOrEmpty(telemetry.Context.Cloud.RoleName))
            {
                //set custom role name here
                telemetry.Context.Cloud.RoleName = "tasksmanager-backend-processor";
            }
        }
    }
}