The following considerations and best practices can help you optimize data movement operations.
- Precise time is necessary for consistent clock synchronization between nodes in ECS. It is strongly recommended to configure and enable NTP service for ECS. By default, Copy to Cloud allows for up to two hours of clock skew for any node. If the clock of any node is skewed more than two hours, some objects may not be copied because their LastModified time (mtime) will be written behind the watermark. Contact your Dell representative if you need to set the minimum watermark lag to a larger value (such as four hours).
- When S3 versioning is disabled on the target bucket, we recommend that the target bucket be dedicated for data movement policies. If an object with the same name exists in the target bucket, Copy to Cloud will overwrite the data in that object.
- Deletes, object tags, and retention lock are not propagated to the target when using Copy to Cloud. For example, if a copied object is deleted from the source ECS, it will remain on the target until it is manually deleted or cleaned by an expiration policy.
- If any data movement copy job experiences a percentage of errors higher than 0%, the data movement service will log an error and send an alert. In this case, copy errors will prevent the watermark from advancing. The data movement policy scan/copy job will stop when the current batch copy completes.
- Copy to Cloud supports up to 100 data movement policies per cluster.
- Copy to Cloud supports copying up to 5TB individual objects.
- Copy to Cloud does not support FS (File System) buckets.
- Copy to Cloud supports copying larger objects using the Multipart-Upload (MPU) capability. For objects larger than 128 MB, you can consider using the Multipart-Upload capability. The default data movement policy scan timeout is one hour, which is not enough to scan a very large object (such as objects larger than 1.8 TB). Contact your Dell representative if you need to increase the data movement policy scan timeout to scan very large objects.
- When TSO is ongoing or happened after 30 minutes on the source ECS, data movement activities will be stopped automatically during any TSO. Data movement activities will be resumed automatically after TSO reconciliation. When PSO has happened on the source ECS, another ECS in the PSO environment will provide data movement services and the data movement engine will ensure that data movement policies work properly.