|About Vocera Clusters / Data Synchronization|
As discussed in Data Synchronization, remote restores and ongoing updates are the two basic mechanisms the Vocera Voice Server uses to synchronize data among cluster nodes. The Vocera Voice Server performs this synchronization automatically; however, there are times when you may want to force the standby nodes to perform a remote restore for the following reasons:
Ongoing updates are effective for propagating incremental changes to standby nodes.
For example, adding and removing users, changing group permissions, and so forth.
Remote restores are more efficient for synchronizing large sets of changes to the database.
For example, importing 5,000 entities, updating users with a spreadsheet, transferring site data, and so forth.
The remote restore is effective for large sets of changes because it reads the entire database of the active node into a standby node's memory in a single operation, and then writes it to the standby node's disk. The ongoing updates process treats every edit as a separate operation.
To use a remote restore to force synchronization to occur:
Similarly, when you first set up a cluster, the best practice is to fully configure the database on the active node, and then bring the standby nodes online. Avoid joining the standby nodes to the cluster before importing large datasets or performing other data-intensive operations. Such operations cause extensive and continual ongoing updates to occur.