This articles covers backup procedures recommended for different types of data including:
- OS and software on the FlashGrid server
- Database files
- Files on ACFS, if used
It is strongly recommended to back up the OS and software volumes after the initial FlashGrid server configuration and before and after applying any changes, such as patch installation or security settings changes. OS and software on a system can be backed up by creating an AMI for the instance or by creating snapshots of individual EBS volumes. AMI-based backup is recommended as it allows easier way to recover an instance in case it is terminated because of a failure or a human error.
To create a backup AMI for a system:
Stop all database instances.
Stop Oracle High Availability Services.
# crsctl stop has
Gracefully stop the instance.
# flashgrid-node poweroff
- Create AMI for the instance.
Note: You can exclude data disks from the AMI to reduce size of the AMI, assuming that data backup is done with RMAN.
IMPORTANT! If data disks are included in the AMI then not stopping HAS services before creating AMI will result in data inconsistency.
Root volume of an instance is an EBS volume that has the OS installed on it. Device name of the root volume is /dev/sda1.
Software volume of an instance is an EBS volume where Oracle software binaries are installed (contains the /u01 directory). Typically the software volume has device name /dev/xvdz.
The root volume or the software volume may need to be restored in case the volume fails, has file system corruption, or has logical corruption.
To restore root volume (sda1) or software volume (xvdz)
In the backup AMI for the affected instance identify the snapshot id for the affected volume
Using the snapshot id, create a new volume in the availability zone where the affected instance is located
Stop the affected instance
- If the OS is running then stop the instance gracefully using flashgrid-node poweroff command
- If the OS is not running then stop the instance using AWS console or CLI
Detach the affected volume from the instance
Attach the newly created volume to the instance using the same device name (/dev/sda1 for root volume, /dev/xvdz for the software volume)
Start the instance
Setting instance termination protection is strongly recommended to prevent accidental termination of an instance.
To restore an instance that was terminated
- Launch a new instance using the backup AMI for the instance that was terminated
- Make sure that correct instance type, VPC, subnet, and security group are selected.
- Configure the same Primary IP that was used on the terminated instance.
- Make sure that only /dev/sda1 and /dev/xvdz volumes are configured. Remove any other volumes if they are present in the AMI.
Attach data volumes to the new instance using the same device names (such as xvdba) that were previously used
Check that HAS services are started, including disk groups:
# crsctl stat res -t
Use standard RMAN procedures for backing up and restoring database files. The two recommended options for backup storage destination are:
- Amazon S3. Provides maximum flexibility with easy shared access to the backup files.
- An EBS volume with a local file system. Provides maximum performance, with up to 500 MB/s of read/write bandwidth on a st1 type of volume.
For information about backing up to S3 see the following documentation from Oracle and AWS:
- White paper: Oracle Database Backup To Cloud: Amazon Simple Storage Service (S3)
- Getting Started with Oracle Secure Backup and RMAN with Amazon S3
- Oracle Secure Backup (OSB) Cloud Module
To configure an EBS volume as a backup storage destination
Create an EBS volume in the availability zone where the instance running RMAN is located. st1 volume type is recommended.
Attach the volume to the instance running RMAN. Select a device name in the xvdc to xvdg range - disks in this name range will not be accessible to ASM.
Format the volume with a local file system (XFS recommended) and create a mount point for it.
Use standard RMAN procedures to configure backup to the local file system.
Note that an EBS volume can be moved only between instances in the same availability zone. However, snapshot of the volume can be used to clone the volume to a different availability zone.
Please follow Grid Infrastructure Backup and Restore Best Practices
For backing up and restoring files on ACFS use same tools and procedures that you would normally use for file-level backup and restore.