Data backup and recovery refers to the processes and procedures used to create copies of data to protect against data loss and restore data if it is lost or corrupted. It is an essential part of any organization’s disaster recovery and business continuity plans.
Why is data backup important?
Data is one of the most valuable assets for any organization. Loss of data can have catastrophic consequences including financial loss, loss of confidence from customers, and damage to reputation. Some key reasons why data backup is critical are:
- Prevent data loss: Backups provide restore points to recover from data loss due to hardware failure, software issues, human errors, malware attacks, natural disasters, etc.
- Meet compliance requirements: Regulations such as SOX, HIPAA, GLBA, etc. require organizations to have backups of key data over specific periods.
- Enable disaster recovery: Backups are essential for recovering systems and continuing operations after outages caused by disasters, ransomware, etc.
- Support business continuity: Easy access to backups facilitates uninterrupted working during planned downtime for maintenance, upgrades, migrations, etc.
What data needs to be backed up?
While ideally all data should be backed up, it may not be practical or required to backup every piece of data. Organizations should identify business critical systems and data that are absolutely essential to restore services after a disruption. Some key items that need to be backed up are:
- Databases: Databases like SQL Server, Oracle, MySQL, MongoDB, etc. containing business transactions, product information, financial data, etc.
- Files: Windows and Linux files servers containing documents, files, folders and shares used enterprise-wide.
- Email: Email servers like Exchange and GroupWise having historical and current emails.
- Desktops/Laptops: User documents, files, settings and configuration stored on end user devices.
- Source code: Code repositories required for building business applications and products.
Types of backups
There are different types of backup processes suited for different requirements:
Full backups
A full backup, also called a complete backup, copies all the data selected for backup. It establishes a baseline and consumes significant storage. Full backups take the longest time to complete but allow for fast and granular restores of data.
Incremental backups
An incremental backup copies data changed since the last full or incremental backup. It is fast and storage-efficient but requires previous backups to restore data. Multiple incremental backups may be required for a complete restore.
Differential backups
A differential backup saves data modified since the last full backup. It strikes a balance between full and incremental backups for speed, storage efficiency and restore granularity.
Reverse Incremental backups
A reverse incremental backup starts with the most recent version of data and moves backwards. Useful for recovering recent data quickly.
Snapshot backups
A snapshot backup creates a point-in-time read-only copy of data rather than copy the actual data files. Useful for backing up large volumes of data like databases.
Synthetic full backups
A synthetic full backup replicates the contents of a full backup using incremental backups. Useful for periodic full backups without taking much time.
How often should backups run?
The frequency of backups depends on factors like:
- Recovery point objective (RPO): The maximum tolerable period of time between backups required to meet business continuity needs.
- Rate of data changes: Backups must be more frequent for systems with high data change rates.
- Regulatory requirements: Regulations may mandate backup frequencies, retention periods etc.
- Costs: Backing up too frequently increases storage costs.
- Type of backup: Full vs. incremental vs. differential.
Typical backup frequencies are:
- Databases – Daily incremental, weekly full.
- Fileservers – Daily incremental, weekly full.
- Email – Daily incremental.
- Desktop/laptop – Daily incremental.
Where are backups stored?
Backups can be stored on disks attached to the source system or external storage. Common backup storage targets include:
- Local disks: Direct-attached storage, storage area network disks, network-attached storage, etc. Low cost but risk of same-site data loss.
- Remote disks: Replicating backups offsite over WAN for protection against local outages. Higher network bandwidth needed.
- Tape: Backups stored on tape cartridges and transported offsite. Secure but requires tape infrastructure.
- Cloud storage: Storing backups on cloud using services like Amazon S3, Azure blob storage, etc. Highly scalable and offsite.
How long should backups be retained?
Retention period depends on:
- Recovery time objective (RTO): The duration within which data must be recovered after an outage.
- Compliance: Regulations may mandate retention rules. Eg. 7 years for financial data.
- Available storage budgets.
Typical retention periods are:
- Daily incremental backups – 1 month
- Weekly full backups – 1 year
- Monthly full backups – 5 years
What is the backup process?
The key steps in the data backup process are:
- Identify data to backup: Assess systems and data to determine backup requirements as per RPO, RTO.
- Select backup type: Choose between full, incremental etc. based on data, frequency, retention needs.
- Choose backup software: Select backup solution software for specific applications, databases, file servers.
- Determine backup schedule: Configure backup frequency, retention policies aligned with RPO, RTO.
- Select backup destination: On-premises disks, tape or cloud storage depending on bandwidth, recovery needs.
- Perform backups: Run backups as per schedule and monitor using logging and alerts.
- Manage backups: Track backup status, perform restore testing, capacity planning as data grows.
- Offsite backups: Replicate backups offsite for protection against site disasters.
How does backup software work?
Backup software performs critical functions including:
- Backup scheduling: Enables setting up backup frequency and policies.
- Backup types: Supports different backup types – full, incremental etc.
- Compression: Reduces backup size through compression to optimize bandwidth and storage.
- Encryption: Encrypts backup data in transit and at rest for security.
- Deduplication: Identifies duplicate data to reduce backup size.
- Bandwidth throttling: Manages network bandwidth to avoid congestion during backups.
- Notifications/reporting: Sends email alerts on backup status and generates reports.
- Automated testing: Validates recoverability of backups through periodic testing.
Backup software integrates with applications like SQL Server, Exchange, MongoDB, Oracle, SharePoint, etc. to facilitate efficient application-consistent backups.
Challenges with backups
Some key backup challenges include:
- Network congestion: Backups consume significant network bandwidth affecting production applications.
- Meeting RTOs: Complicated to meet tight recovery time objectives with larger full backups.
- Increased costs: Backup storage and network capacity must expand alongside data growth.
- Complexity: Demands skilled staff to configure, monitor, troubleshoot backups across environments.
- Encryption overhead: Backup encryption impacts application performance and increases backup times.
- Compliance risks: Gaps in backup compliance related to retention, encryption, offsite replication etc.
Data recovery process
The key steps in the data recovery process are:
- Identify restore need: Determine the impacted systems, data loss, recovery points required.
- Locate backups: Identify the relevant full as well as incremental backups required for restore.
- Select recovery point: Choose the appropriate backup set to meet the desired RTO.
- Prepare infrastructure: Provision resources like servers, networks matching the target environment.
- Restore backups: Restore backups sequentially starting from full backups to the desired point in time.
- Verify restore: Validate completeness and integrity of the restored data.
- Synchronize data: Replicate restored data to redundant site if needed.
Granular recovery techniques
Granular recovery refers to restoring individual application objects like emails, database tables, documents etc. instead of entire volumes. Key techniques for granular recovery include:
Application snapshots
Snapshot copies allow restoring database tables, user mailboxes from specific points in time.
Backup indexing
Indexing backups at object level enables searching and recovering individual files, messages efficiently.
Object deduplication
Deduplicating objects like files, mailbox items during backup improves restore speeds for individual items.
Instant recovery
Instant recovery presents backups as virtual disks to instantly access individual files for recovery.
Testing backup recoverability
Verifying the recoverability of backups is essential for building confidence in DR plans. Key steps include:
- Recovering backups to a test/staging environment matching production infrastructure.
- Executing test restores from different points in time – full, incremental, snapshot backups.
- Testing granular restore capabilities for individual data objects.
- Validating application consistency of database restores.
- Measuring restore times to meet RTO.
- Reviewing logs, alerts generated during the restore process.
- Tuning backup configurations based on test results.
Maintaining the backup environment
Effective maintenance of the backup environment involves:
- Monitoring – Tracking backup status, failures, schedule deviations using log monitoring.
- Notifications – Email alerts on backup status to designated IT teams.
- Reporting – Generating backup reports periodically with key metrics like success %, storage usage.
- Labeling – Standards for labeling backups with version, dates for ease of administration.
- Testing – Regular backup testing to validate recoverability.
- Retention management – Processes for maintaining retention policies, refreshing tapes, etc.
- Capacity planning – Forecasting additional backup storage needs based on data growth trends.
- Security – Backup encryption, role-based access, backup deletion as per security protocols.
Emerging backup trends
Key trends shaping backup technology and processes include:
- Cloud backup – Backup solutions using public cloud storage services.
- SaaS backup – Backup offered as a service rather than on-premises software.
- Immutable storage – Makes backup data unchangeable improving security and compliance.
- Instant recovery – Using snapshots and clones to quickly restore systems.
- Automation – Scripting and orchestrating backup administration for efficiency.
- Unified data management – Converged solutions for availability, replication, archiving beyond just backup.
- Intelligent diagnosis – ML-driven insights into backup environments for preventive management.
- As a service DR – Offsite replication and automated DR orchestration using cloud.
Key considerations for backup strategy
Developing an organizational backup strategy involves several important considerations:
- Prioritizing systems and data for backup aligned to business criticality.
- Selection of backup types – incremental, differential or a blend – to balance costs, recovery goals.
- On-premises vs. cloud backup to optimize recoverability, compliance and TCO.
- Network bandwidth optimization for faster backups that don’t disrupt operations.
- Automated monitoring and testing to ensure backup environments meet backup SLAs.
- Viewing backup as part of the larger data management ecosystem including archival, compliance and DR.
- Processes for capturing new application workloads like containers into the data protection strategy.
- Roadmap to transform backup management from reactive to proactive using AI/ML tools.
Conclusion
Data backup is a core function for mitigating data loss risks and meeting demanding recovery objectives. Organizations must develop well-rounded backup strategies encompassing offsite replication, granular recovery capabilities, immutable storage, cloud adoption and automation. Testing backups regularly and monitoring backup environments vigilantly is vital. With powerful new technologies and solutions emerging, there are tremendous opportunities to advance data protection strategies significantly.