The following is a slightly modified repost from synametrics.com, total credit goes to them. IMO, it is the best Firebird installation anywhere one can find on the Internet for older Firebird versions.

Firebird is derived from Borland InterBase 6.0 source code. For phpGrid, you can use either 'odbc' or 'ibase' as the driver type. 

This KB is for using ODBC driver. 

Download and installation

The older Firebird versions can be downloaded from firebirdsql.org <-- direct link. 

There are two different architectures for the RDBMS itself: Classic and SuperServer. In this KB, the SuperServer architecture will be covered. Both the RDBMS and the ODBC driver installation are rather simple. During setup, there are no configuration-related parameters. 

Make that the Firebird service is running when the setup is finished.

Configuring the ODBC driver

In this example, we will be connecting to the Employee database that comes as an example with Firebird.

Follow the steps below to create a new DSN for firebird.

1. Start ODBC Data Source Administrator from the Control Panel
2. Select the Drivers tab and ensure that Firebird/InterBase driver is listed among available driver
3. Select either System DSN or User DSN and click Add button
4. Pick Firebird/InterBase driver and click Finish
5. The next screen prompts you to enter Firebird specific details and is shown below.
   
   
   
   
6. Finally click Ok

The following table discusses some important parameters required during ODBC setup

Data Source Name: This field identifies the data source

Database: This is the most important piece of information and is often mistyped by new users. Since we are using the SuperServer architecture, this field expects a host name, TCP/IP port, and the file name representing the database. The format of this string is HostName/Port:FileName . You can omit the TCP/IP port number if the server is listening on the default port, which is 3050. For file name you can either use UNIX style or Windows style separators.

Client: Leave this blank. This is only required for embedded servers.

Database Account: This is the login ID. Try using SYSDBA, which is a pre-built account that comes with Firebird

Password: The default password for SYSDBA is masterkey

Role: Leave this blank, particularly if you are using the SYSDBA account.

Default Values

Following table lists values for some important parameters in Firebird database.

TCP/IP Port: 3050

Login ID: SYSDBA

Password: masterkey

System database name: None - all system tables are stored in the user database

Security

Firebird's default login account is SYSDBA with the password masterkey. A unique database called "security2.fdb" houses all security-related data. ODBC cannot programmatically access this database using Firebird. Therefore, you are unable to conduct SQL queries to edit or create new users. "gsec.exe," a command-line user management tool included with Firebird, may be found in the Bin folder. 

The ODBC Driver setup screen may be used to manage users as well. On the Firebird ODBC setup page, click the Services button, then select the Users tab.

More further information about security in Firebird, refer to http://www.firebirdsql.org/manual/firebird-database-documentation.html

Original Post:
https://web.synametrics.com/firebird.htm