- Backups and Restoring Cloud Data
- Implement a Disaster Recover Plan
- Implement a Business Continuity Plan
Main Backup Types:
Full – Complete backup on an entire data set.
Incremental – Backs up data that has been changed since last backup.
Differential – Back ups all of the data that has changed since the last full backup (incremental backups only include the data that was changed since the previous backup).
Cloud-Specific Backup and Restore Types:
Copy-on-Write Snapshot – Stores metadata about the location of the original data without copying it when the snapshot is created. This enables rapid recovery of data in case of a disk write error, corrupt file(s), or program errors.
Clone or Split-Mirror Snapshot – Backups from a set of mirrored drives.
Redirect-on-Write Storage Snapshot – Similar to copy-on-write, but writes only changed data that is redirected to storage that is provisioned for snapshots (eliminates the need for two writes).
Incremental Snapshot – Creates timestamps that allows users to go back to a point in time.
Change Block Tracking – VMWare uses a incremental backup method called Changed Block Tracking (CBT). Checks blocks that have been modified and backs up that specific data instead of entire disk.
Types of Storage for Backups
Direct-Attached-Storage (DAS) – Digital storage device that is directly attached to a computer.
Network-Attached-Storage (NAS) – Digital storage device that is connected to a local network.
Storage-Area-Network (SAN) – Dedicated pools of shared storage on a network that interconnects to multiple servers.
Cloud – Backs up data from an on-premise site to a cloud datacenter. Depending on provider, this may be a managed or an unmanaged service. Data in the cloud can be easily replicated from one storage location (region) to another.
An online backup is where data is regular backed up on a remote server or in the cloud. Also called a web-based backup
Offline backup is also known as a cold backup and is performed when a system is offline (often used for database backups to avoid data processing during the backup process).
Recovery Point Objective (RPO) – The point in time you hope to recover after a disaster. Recovery point objectives refer to your company’s loss tolerance: the amount of data that can be lost before significant harm to the business occurs. The objective is expressed as a time measurement from the loss event to the most recent preceding backup.
Recovery Time Objective (RTO) – The length of time it takes to restore data.
Disaster Recovery (DR) Capabilities in the Cloud
- Backup to and restore from the cloud
- Backup to and restore to the cloud
- Replication to virtual machines in the cloud
- Managed applications and managed DR in the cloud by cloud providers
- File transfer
- Third party sites
- Customized SLAs that meet business requirements and policies for Disaster Recovery (DR)
- Disaster Recovery-as-a-Service (DRaaS) – Paid service that is managed by cloud providers.
Business Continuity Plan
A business continuity plan should contain the following:
- Initial data including important contact information
- Revision management that describes change management procedures
- Purpose and scope
- Policy information
- Emergency response and management
- Step-by-step procedures
- Checklists and flow diagrams
- Schedule to review current plan, testing, and updating the plan
Alternate DR Sites
Alternate sites should be considered when creating a business continuity plan and should have the following:
- Physical location of the alternate site.
- Will it be able to support the needed technology and infrastructure?
- Will it be a cold, warm, or hot site (referring to data transfers)?