Using ClickHouse-Backup for Comprehensive ClickHouse® Backup and Restore Operations

ClickHouse® has become a cornerstone technology for organizations handling massive analytical workloads, but with great data comes great responsibility for backup and disaster recovery. The clickhouse-backup tool emerges as the de facto standard for managing ClickHouse backups, offering robust functionality for both local and cloud-based backup strategies.

What is ClickHouse-Backup?

clickhouse-backup is an open-source backup utility specifically designed for ClickHouse databases. Developed by Altinity, this tool provides comprehensive backup and restore capabilities that go beyond simple data dumps, supporting incremental backups, compression, and multiple storage backends including local filesystems, AWS S3, Google Cloud Storage, and Azure Blob Storage.

Key Features and Capabilities

• Incremental and full backups with automatic deduplication
• Multi-storage backend support (S3, GCS, Azure, FTP, SFTP)
• Compression algorithms including gzip, lz4, brotli, and zstd
• Parallel processing for improved backup performance
• Metadata preservation including table schemas and configurations
• Cluster-aware operations for ClickHouse clusters
• Encryption support for secure backup storage

Installation and Setup

Installing ClickHouse-Backup

The installation process varies depending on your environment:

# Using Docker (recommended)
docker pull altinity/clickhouse-backup:latest

# Using pre-built binaries
wget https://github.com/Altinity/clickhouse-backup/releases/latest/download/clickhouse-backup-linux-amd64.tar.gz
tar -xzf clickhouse-backup-linux-amd64.tar.gz
sudo mv clickhouse-backup /usr/local/bin/

# Building from source
git clone https://github.com/Altinity/clickhouse-backup.git
cd clickhouse-backup
make build

Configuration Setup

Create a configuration file at /etc/clickhouse-backup/config.yml:

general:
  remote_storage: s3
  max_file_size: 1073741824
  disable_progress_bar: false
  backups_to_keep_local: 0
  backups_to_keep_remote: 0

clickhouse:
  username: default
  password: ""
  host: localhost
  port: 9000
  disk_mapping: {}
  skip_tables:
    - system.*
  timeout: 5m

s3:
  access_key: "YOUR_ACCESS_KEY"
  secret_key: "YOUR_SECRET_KEY"
  bucket: "your-backup-bucket"
  endpoint: ""
  region: us-east-1
  acl: private
  force_path_style: false
  path: "clickhouse-backups/"
  disable_ssl: false
  compression_level: 1
  compression_format: gzip

Creating Backups

Full Database Backup

Execute a complete backup of your ClickHouse instance:

# Create local backup
clickhouse-backup create full_backup_$(date +%Y%m%d_%H%M%S)

# Create and upload to remote storage
clickhouse-backup create_remote full_backup_$(date +%Y%m%d_%H%M%S)

Table-Specific Backups

Target specific tables or databases for more granular control:

# Backup specific tables
clickhouse-backup create --tables=database1.table1,database2.table2 selective_backup

# Backup entire database
clickhouse-backup create --schema --data --database=analytics_db db_backup

Incremental Backup Strategy

Implement incremental backups to optimize storage and transfer times:

# Create base backup
clickhouse-backup create base_backup

# Create incremental backup (only changed data)
clickhouse-backup create --diff-from=base_backup incremental_backup_001

Advanced Backup Configurations

Compression and Performance Optimization

Configure compression settings for optimal performance:

general:
  compression_format: zstd
  compression_level: 3
  upload_concurrency: 8
  download_concurrency: 4

s3:
  part_size: 104857600  # 100MB parts for multipart uploads
  max_parts_count: 10000

Backup Scheduling with Cron

Automate backup operations using cron jobs:

# Add to crontab
# Daily full backup at 2 AM
0 2 * * * /usr/local/bin/clickhouse-backup create_remote daily_$(date +\%Y\%m\%d) && /usr/local/bin/clickhouse-backup delete local daily_$(date -d '7 days ago' +\%Y\%m\%d)

# Hourly incremental backups
0 * * * * /usr/local/bin/clickhouse-backup create_remote --diff-from=daily_$(date +\%Y\%m\%d) hourly_$(date +\%Y\%m\%d_\%H)

Restore Operations

Complete Database Restore

Restore your entire ClickHouse instance from backup:

# List available backups
clickhouse-backup list remote

# Download and restore backup
clickhouse-backup download backup_name
clickhouse-backup restore backup_name

# Direct restore from remote storage
clickhouse-backup restore_remote backup_name

Selective Table Restore

Restore specific tables without affecting the entire database:

# Restore specific tables
clickhouse-backup restore --tables=database1.table1,database2.table2 backup_name

# Restore to different table names
clickhouse-backup restore --tables=source_db.source_table:target_db.target_table backup_name

Point-in-Time Recovery

Implement point-in-time recovery using incremental backups:

# Restore base backup
clickhouse-backup restore base_backup

# Apply incremental backups in sequence
clickhouse-backup restore --diff-from-remote=base_backup incremental_backup_001
clickhouse-backup restore --diff-from-remote=incremental_backup_001 incremental_backup_002

Monitoring and Maintenance

Backup Verification

Regularly verify backup integrity:

# Verify local backup
clickhouse-backup list local

# Check remote backup status
clickhouse-backup list remote

# Validate backup contents
clickhouse-backup check backup_name

Cleanup and Retention Policies

Implement automated cleanup to manage storage costs:

general:
  backups_to_keep_local: 3
  backups_to_keep_remote: 30

# Manual cleanup
clickhouse-backup clean_remote_broken
clickhouse-backup delete local old_backup_name

Performance Monitoring

Monitor backup performance and optimize accordingly:

# Enable verbose logging
clickhouse-backup --log-level=debug create backup_name

# Monitor backup progress
clickhouse-backup --progress create backup_name

Best Practices and Security

Security Considerations

1. Encrypt sensitive backups using storage-level encryption
2. Implement access controls with IAM policies for cloud storage
3. Use secure credential management (avoid hardcoded secrets)
4. Enable audit logging for backup operations

Performance Optimization

1. Configure appropriate compression based on CPU vs. storage trade-offs
2. Optimize concurrent operations based on network bandwidth
3. Use incremental backups for large datasets
4. Schedule backups during low-activity periods

Disaster Recovery Planning

1. Test restore procedures regularly in isolated environments
2. Document recovery time objectives (RTO) and recovery point objectives (RPO)
3. Maintain geographically distributed backups for disaster resilience
4. Automate failover procedures where possible

Troubleshooting Common Issues

Connection Problems

# Test ClickHouse connectivity
clickhouse-backup list local --config=/path/to/config.yml

# Verify credentials and permissions
clickhouse-backup check-config

Storage Issues

# Check available disk space
df -h /var/lib/clickhouse/

# Verify remote storage connectivity
clickhouse-backup list remote --config=/path/to/config.yml

Performance Issues

# Monitor backup progress
tail -f /var/log/clickhouse-backup.log

# Adjust concurrency settings
clickhouse-backup create --upload-concurrency=4 backup_name

Conclusion

ClickHouse-backup provides a robust, enterprise-grade solution for protecting your ClickHouse data assets. By implementing proper backup strategies, monitoring procedures, and disaster recovery plans, organizations can ensure business continuity while maintaining optimal performance for their analytical workloads.

The tool’s flexibility in supporting various storage backends, compression algorithms, and backup strategies makes it suitable for organizations of all sizes, from startups to large enterprises managing petabytes of analytical data.

Regular testing of backup and restore procedures, combined with automated monitoring and alerting, ensures that your ClickHouse infrastructure remains resilient against data loss scenarios while meeting your organization’s specific recovery requirements.

Further Reading:

Avoiding ClickHouse Fan Traps : A Technical Guide for High-Performance Analytics

Open Source Data Warehousing and Analytics

Implementing Data Level Security on ClickHouse: Complete Technical Guide

ClickHouse ReplacingMergeTree Explained

Building Fast Data Loops in ClickHouse®