Feature #11766: rbd-mirror: basic structure
New RBD notification pool object for recording mirroring errors
There are multiple possible failures that could occur during runtime with mirroring. There needs to be a way to alert the operator of these errors without scanning log files. When the RBD mirroring daemon encounters an error with an image, it should register an alert in this pool object and send a "update" notify. The rbd CLI should be expanded to watch this file and dump its contents.