Auxiliary Copy - Best Practices
Enabling Dynamic Stream Allocation
The dynamic stream allocation is enabled by default in the current software version. However, if you have upgraded to the current version, it is recommended to enable Distribute data evenly among multiple streams for offline read operations when you want to copy large amount of data to a tape library. You can enable it as described in Configuring Dynamic Stream Allocation.
Few other scenarios in which you should enable Distribute data evenly among multiple streams for offline read operations are given below:
- Multiple Storage Policies are using same library and auxiliary copy jobs for all the storage policies are scheduled at the same time.
- Some drives from the tape library are offline for long time.
Combining Streams Using Multiplexing
For Auxiliary Copy operations in a tape environment, you can utilize streams and tape resources more effectively by enabling Combine Source Data Streams and Multiplex source streams options on a secondary copy.
Avoiding Media Contention
If many backup and restore jobs are using the same storage policy, it may cause the media contention. This affects the performance of each job. To avoid this situation, before starting an auxiliary copy operation for a storage policy, ensure that the storage policy is not used by any other backup or restore jobs. Perform the following before starting an auxiliary copy operation:
- To Identify the Storage Policy associated with any backup or restore job, view the Storage Policy column in the Job Controller.;
- To view all the jobs scheduled for a storage policy, right-click the storage policy and select View | Schedules.
Reducing Level of Multiplexing
If you are using data multiplexing while creating the Primary copy and if all the data from the Primary copy is not included in a secondary copy, then the auxiliary copy operation will become slower. To improve the performance of the auxiliary copy operation, it is recommended to reduce multiplexing factor for the primary copy.
Avoiding Streams with Partially Copied Data in the Waiting State
When running auxiliary copy operation to all the parallel copies configured in the storage policy, we recommend that the source and the destination MediaAgent should be same to avoid streams with partially copied data in the waiting state.
Viewing the Status of Auxiliary Copy Operations for a Client
You can ensure that your client is ready for a disaster recovery by verifying that all the backed up data for the client are copied to a secondary copy.
You can view the status of the auxiliary copy operations for the client from the following locations:
- Client Summary Screen
The Readiness Status: option in the client summary screen on the CommCell Console displays the status of the auxiliary copy operations for a client.
For an overview on the client summary screen, see Navigation Pane.
The following table lists the available status messages for the client:
Message Description Ready All the client's data on the primary copy of the associated storage policies are copied to the secondary copies. This message is also displayed if there are no secondary copies. Behind Schedule. Auxiliary Copy job time is not available You have created secondary copies but never ran any auxiliary copy operations for the associated storage policies. On Schedule. Auxiliary Copy job time estimated to be up to n hours/days. You have partially copied the data and the time estimated for an auxiliary copy operation to copy the remaining data is less than or equal to n hours or days.
The estimated time is calculated based on the average throughout of previous auxiliary copy jobs. The message displays On Schedule when the estimated time n is less than 48 hours.
Behind Schedule. Auxiliary Copy job time estimated to be up to n days. You have partially copied the data and the time estimated for an auxiliary copy operation to copy the remaining data is less than or equal to n days.
The estimated time is calculated based on the average throughout of previous auxiliary copy jobs. The message displays Behind Schedule when the estimated time n is greater than 48 hours.
- Health Report
The Fallen Behind Secondary Copies parameter in the health report includes a DR Ready as of: column that displays the approximate date when all the client's data on the primary copy of the associated storage policies are copied to the secondary copies.
For more information , see Health Report - Fallen Behind Secondary Copies.