Time-critical database condition data handling in the CMS experiment during the first data taking period

Automatic, synchronous and of course reliable population of the condition databases is critical for the correct operation of the online selection as well as of the offline reconstruction and analysis of data. In this complex infrastructure, monitoring and fast detection of errors is a very challenging task. To recover the system and to put it in a safe state requires spotting a faulty situation within strict time constraints. We will describe here the system put in place in the CMS experiment to automate the processes that populate centrally the Condition Databases and make condition data promptly available both online for the high-level trigger and offline for reconstruction. The data are automatically collected using centralized jobs or are ``dropped'' by the users in dedicate services (offline and online drop-box), which synchronize them and take care of writing them into the online database. Then they are automatically streamed to the offline database, and thus are immediately accessible offline worldwide. The condition data are managed by different users using a wide range of applications, each having a different role to play. In normal operation the system that monitors the database is used to provide simple timing information and the history of all transactions for all database accounts, and in the case that faults occur it is used to return simple error messages and more complete debugging information.