Keeping active volumes consistent up to a given time is an important function of XRC support. Data integrity depends on ensuring that updates occur on the secondary volumes in the same order as they occurred on the primary volumes. This update sequencing is necessary in order to avoid data integrity problems and data loss. Maintaining data integrity becomes especially critical when multiple applications update a volume, or when a data set exists on multiple volumes that are spread across multiple storage controls.
The timestamp reported by the consistency group time is the primary system timestamp up to which the data on XRC active volumes is consistent. The following commands generate messages that report the consistency group time: