pgmoneta

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Introduction ​

pgmoneta is a backup / restore solution for PostgreSQL.

Ideally, you would not need to do backups and disaster recovery, but that isn't how the real World works.

Possible scenarios that could happen

  • Data corruption
  • System failure
  • Human error
  • Natural disaster

and then it is up to the database administrator to get the database system back on-line, and to the correct recovery point.

Two key factors are

  • Recovery Point Objective (RPO): Maximum targeted period in which data might be lost from an IT service due to a major incident
  • Recovery Time Objective (RTO): The targeted duration of time and a service level within which a business process must be restored after a disaster (or disruption) in order to avoid unacceptable consequences associated with a break in business continuity

You would like to have both of these as close to zero as possible, since RPO of 0 means that you won't lose data, and RTO of 0 means that your system recovers at once. However, that is easier said than done.

pgmoneta is focused on having features that will allow database systems to get as close to these goals as possible such that high availability of 99.99% or more can be implemented, and monitored through standard tools.

pgmoneta is named after the Roman Goddess of Memory.

Features ​

  • Full backup
  • Restore
  • Compression (gzip, zstd, lz4, bzip2)
  • AES encryption support
  • Symlink support
  • WAL shipping support
  • Hot standby
  • Prometheus support
  • Remote management
  • Offline detection
  • Transport Layer Security (TLS) v1.2+ support
  • Daemon mode
  • User vault

pgmoneta has a Model Context Protocol server called pgmoneta_mcp.

Platforms ​

The supported platforms are

Migration ​

From 0.20.x to 0.21.0 ​

Backup Rate Limit Configuration ​

Rate-limit configuration for backups has been consolidated.

This is a breaking change for existing configuration files.

backup_max_rate and network_max_rate are no longer valid keys and have been replaced by a single max_rate key.

max_rate is configured in bytes per second.

Action required:

  1. Update pgmoneta.conf and replace old keys:
    • backup_max_rate
    • network_max_rate
  2. Set max_rate instead (globally and/or per-server).
  3. Reload or restart pgmoneta.

Example:

conf
max_rate = 1000000

Vault Encryption ​

The key derivation for vault file encryption has been upgraded to PKCS5_PBKDF2_HMAC (SHA-256, random 16-byte salt, 600,000 iterations).

This is a breaking change. Existing vault files encrypted with the old method cannot be decrypted by version 0.21.0.

Action required:

  1. Stop pgmoneta
  2. Delete the existing user files:
    • pgmoneta_users.conf
    • pgmoneta_admins.conf
    • Vault users file (if applicable)
  3. Delete the existing master key:
    rm ~/.pgmoneta/master.key
  4. Regenerate the master key:
    pgmoneta-admin master-key
  5. Re-add all users:
    pgmoneta-admin user add -f <users_file>
  6. Restart pgmoneta