Overcast storage is designed to provide 99.999999999% durability. This durability level corresponds to an average annual expected loss of 0.000000001%. To put that in context, if you store 10,000 objects, you can on average expect to incur a loss of a single object once every 10,000,000 years. In addition, our Amazon storage facility is designed to sustain the concurrent loss of data in two facilities.
Overcast objects are redundantly stored on multiple devices across multiple facilities in Ireland. The storage service is designed to sustain concurrent device failures by quickly detecting and repairing any lost redundancy. When processing a request to store data, the service will redundantly store your object across multiple facilities before returning SUCCESS.
As with any environment, the best practice is to have a backup and to put in place safeguards against malicious or accidental users errors. For Overcast data, that best practice includes secure access permissions, cross-region replication and regularly tested backup.