You can't run an application stably without monitoring. Monitoring lets you figure out whether the changes you made were good or bad. It lets you respond with information rather than with panic, when one of your end users complains that your application is down. Stackdriver is GCP's tool for monitoring, logging and diagnostics. Stackdriver gives you access to many different kinds of signals from your infrastructure platforms, virtual machines, containers, middleware and application tier, logs, metrics and traces. It gives you insight into your application's health, performance and availability. So if issues occur, you can fix them faster. Here are the core components of Stackdriver: Monitoring, Logging, Trace, Error Reporting and Debugging. Stackdriver Monitoring checks the endpoints of web applications and other Internet accessible services running on your cloud environment. You can configure uptime checks associated with URLs, groups or resources such as Instances and load balancers. You can set up alerts on interesting criteria, like when health check results or uptimes fall into levels that need action. You can use Monitoring with a lot of popular notification tools. And you can create dashboards to help you visualize the state of your application. Stackdriver Logging lets you view logs from your applications and filter and search on them. Logging also lets you define metrics, based on log contents that are incorporated into dashboards and alerts. You can also export logs to BigQuery, Cloud Storage and Cloud PubSub. Stackdriver Error Reporting tracks and groups the errors in your cloud applications. And it notifies you when new errors are detected. With Stackdriver Trace, you can sample the latency of app engine applications and report Per-URL statistics. How about debugging? A painful way to debug an existing application is to go back into it and add lots of logging statements. Stackdriver Debugger offers a different way. It connects your applications production data to your source code. So you can inspect the state of your application at any code location in production. That means you can view the application stage without adding logging statements. Stackdriver Debugger works best when your application source code is available, such as in Cloud Source repositories. Although it can be in other repositories too.
