ATLAS Tier-2 monitoring system for the German cloud

The ATLAS tier centers in Germany provide their computing resources for the ATLAS experiment. The stable and sustainable operation of this so-called DE-cloud heavily relies on effective monitoring of the Tier-1 center GridKa and its associated Tier-2 centers. Central and local grid information services constantly collect and publish the status information from many computing resources and sites. The cloud monitoring system discussed in this presentation evaluates the information related to different cloud resources and provides a coherent and comprehensive view of the cloud. The main monitoring areas covered by the tool are data transfers, cloud software installation, site batch systems, Service Availability Monitoring (SAM). The cloud monitoring system consists of an Apache-based Python application, which retrieves the information and publishes it on the generated HTML web page. This results in an easy-to-use web interface for the limited number of sites in the cloud with fast and efficient access to the required information starting from a high level summary for the whole cloud to detailed diagnostics for the single site services. This approach provides the efficient identification of correlated site problems and simplifies the administration on both cloud and site level.