DLM Administration
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How Policies Work in Data Lifecycle Manager

In Data Lifecycle Manager, you create policies to establish the rules you want applied to your replication and disaster recovery jobs. The policy rules you set can include which cluster is the source and which is the destination, what data is replicated, what day and time the replication job occurs, the frequency of job execution, and bandwidth restrictions.

When scheduling how often you want a replication job to run, you should consider the recovery point objective (RPO) of the data being replicated; that is, what is the acceptable lag time between the active site and the replicated data on the destination. Data Lifecycle Manager supports a one-hour RPO: data is preserved up to one hour prior to the point of data recovery. To meet a one-hour RPO, you must consider how long it takes to replicate the selected data, how often the data is replicated, and network bandwidth capabilities.

As an example, if you have a set of data that you expect to take 15 minutes to replicate, then to meet a one-hour RPO, you would schedule the replication job to occur no more often than every 45 minutes, depending on network bandwidth.

  • The first time you execute a job (an instance of a policy) with data that has not been previously replicated, Data Lifecycle Manager creates a new folder or database and bootstraps the data.

    During a bootstrap operation, all data is replicated from the source cluster to the destination. As a result, the initial execution of a job can take a significant amount of time, depending on how much data is being replicated, network bandwidth, and so forth. So you should plan the bootstrap accordingly.

    After initial bootstrap, data replication is performed incrementally, so only updated data is transferred. Data is in a consistent state only after incremental replication has captured any new changes that occurred during bootstrap.

  • Achieving a one-hour Recovery Point Objective (RPO) depends on how you set up your replication jobs and the configuration of your environment:
    • Select data in sizes that replicate within 30 minutes.
    • Set replication frequency to 45 minutes or less.
    • Ensure that network bandwidth is sufficient, so that data can move fast enough to meet your RPO.
    • Consider the rate of change of data being replicated.