Firebird

Firebird is an open-source relational database. DBackup supports Firebird backups using the native gbak backup/restore utility.

Supported Versions

Versions
3.x, 4.x, 5.x

Legacy versions

Firebird 2.5 and the legacy .gdb file format are not supported.

Connection Modes

Mode	Description
Direct	DBackup runs gbak/isql locally and connects to the remote Firebird server over its wire protocol (port 3050)
Over SSH	DBackup connects via SSH and runs gbak/isql on the remote host, reading the local .fdb path directly

Architecture

Firebird has no server-side "list all databases" command - every .fdb file is a standalone database with no central registry to query. Because of this, a Firebird source works differently from other adapters in one respect:

• You enter a list of database aliases once, when creating the source: an alias name (shown everywhere else in DBackup) mapped to the actual file path on the Firebird server.
• Everywhere else is unchanged - the job form's database picker, the backup pipeline, and the restore UI all work with these alias names exactly like they would with any other adapter's database list.
• If a new database is added to the Firebird server later, it won't appear automatically - add its alias and path to the source configuration.

Configuration

Credential Profiles

A USERNAME_PASSWORD credential profile is required for the SYSDBA (or equivalent) user. SSH mode additionally requires an SSH_KEY profile.

Field	Description	Default	Required
How DBackup connects	Direct or Over SSH	-	✅
Host	Firebird server hostname or IP	localhost	✅
Port	Firebird server port	3050	✅
Login	USERNAME_PASSWORD credential profile	-	✅
Aliases	List of { name, path } entries - the alias shown in DBackup and the .fdb path on the Firebird server	-	✅ (at least one)
Extra options	Extra gbak flags	-	❌

SSH Mode Fields

These fields appear in the SSH server part when How DBackup connects is set to Over SSH:

Field	Description	Default	Required
SSH host	SSH server hostname or IP	-	✅
Port	SSH server port	22	❌
SSH login	SSH_KEY credential profile (username + key or password)	-	✅

Paths in SSH Mode

In SSH mode, database paths are local paths on the SSH target, since gbak runs there directly - not paths as seen from the Firebird server's own network. In Direct mode, paths are as seen from the Firebird server (aliases the server itself resolves).

Example Configuration

Direct Mode

Host: firebird.example.com
Port: 3050
Login: my-firebird-sysdba  (USERNAME_PASSWORD profile)
Database Aliases:
  erp  -> /data/erp.fdb
  crm  -> /data/crm.fdb

SSH Mode

SSH Host: firebird.example.com
SSH login: my-firebird-ssh-key  (SSH_KEY profile)
Database Aliases:
  erp  -> /var/lib/firebird/data/erp.fdb

Backup File Format

• Single alias selected: stored directly as a .fbk file (gbak's native backup format) - no archive wrapper
• Multiple aliases selected: packed into a TAR archive containing one .fbk file per database plus a manifest

With compression and encryption enabled:

• Single database: backup_2026-02-02.fbk.gz.enc
• Multiple databases: backup_2026-02-02.tar.gz.enc

Restore Limitations

Restore is scoped to pre-configured aliases

Because a Firebird alias has no meaning without a matching file path, restore only lets you pick among the aliases already configured on the target source (shown as a dropdown) - you cannot restore into an arbitrary new database name. To restore into a new location, add its alias and path to the target source first, then restore into it.

Restoring always replaces the target file's contents (gbak -rep) - there's no separate "create only" step, so make sure you're restoring into the intended alias.

DBackup also blocks restoring a backup taken on a newer Firebird version onto an older target server, consistent with the version guard used by other adapters.

Required CLI Tools

The Firebird adapter requires gbak (backup/restore) and isql (connection test/version check).

Direct Mode

Already included in the DBackup Docker image.

Manual Installation: install the Firebird client tools matching your distribution, or download the official release from the Firebird project.

SSH Mode

gbak and isql must be installed on the remote SSH server:

# Debian/Ubuntu (client package version may lag behind the latest server release)
apt-get install firebird3.0-utils

Important

In SSH mode, gbak/isql must be installed on the remote server. DBackup executes them remotely via SSH and streams the backup output back.

Troubleshooting

Unknown Database Alias

Unknown Firebird database alias "accounting". Configured aliases: erp, crm.

Solution: Add the missing alias and its .fdb path to the source configuration, or pick one of the listed aliases.

Connection Refused

Ensure the Firebird server is listening on the configured port and accepts remote connections (check firebird.conf / RemoteBindAddress).

SSH: Binary Not Found

Required binary not found on remote server. Tried: gbak

Solution: Install the Firebird client tools on the remote server (see above).

Restore Blocked by Version Guard

Running restore of a newer database version on an older server is not recommended...

Solution: Restore onto a Firebird server running the same or a newer version than the one the backup was taken on.

See Also

• Backups - Browse and download backups
• Restore Guide - General restore documentation
• Encryption - Encrypting your backups