freeTDS not using its config

khartvin picture khartvin · Oct 25, 2012 · Viewed 55.5k times · Source

I've decided to use FreeTDS driver and unixODBC to manage the PDO connection between my LAMP-based app with a remote MsSQL database. unfortunately it appears that the driver doesn't read the freetds.conf file, nor the environmental variables set either directly via server's CLI or specified in php file by putenv() function.

now some data:

  1. as I ping the server - no packets are lost.
  2. as I telnet the server on 1433 port - the connection is established
  3. as I use the command

    TDSVER=7.0 tsql -H >IP< -p 1433 -U username
    

    I am prompted to enter password and connection is established.

  4. without the TDSVER preceding the command - the connection fails with such a message:

    Error 20017 (severity 9):
        Unexpected EOF from the server
        OS error 115, "Operation now in progress"
    Error 20002 (severity 9):
        Adaptive Server connection failed
    There was a problem connecting to the server
    
  5. the tsql -C commands echos such an output:

    Compile-time settings (established with the "configure" script)
                           Version: freetds v0.91
            freetds.conf directory: /usr/local/etc
    MS db-lib source compatibility: yes
       Sybase binary compatibility: no
                     Thread safety: yes
                     iconv library: yes
                       TDS version: 5.0
                             iODBC: no
                          unixodbc: yes
             SSPI "trusted" logins: no
                          Kerberos: no
    
  6. freetds.conf in the location given above has this entry:

    [MSSQL]
    host = >IP<
    port = 1433
    tds version = 7.0
    
  7. the ISQL also fails:

    isql -v MSSQL
    [S1000][unixODBC][FreeTDS][SQL Server]Unable to connect to data source
    [01000][unixODBC][FreeTDS][SQL Server]Adaptive Server connection failed
    [ISQL]ERROR: Could not SQLConnect
    
  8. my odbc.ini :

    [MSSQL]
    Description = MS SQL Server
    Driver = FreeTDS
    TDS_Version = 7.0
    Server = >IP<
    UID = username
    PWD = password
    ReadOnly = No
    Port = 1433
    

I suppose the solution is really simple, but i'm just too stupid to find it...

Answer

Max Bolingbroke picture Max Bolingbroke · Apr 25, 2013

I spent a long time today debugging a similar problem. I had set "TDS version" in freetds.conf but it was not being used in my ODBC connection. After reading the freetds source code (connectparams.c:odbc_parse_connect_string) I discovered that:

  • If your connection string uses "SERVER=" then both freetds.conf and odbc.ini are ignored
  • If your connection string uses "SERVERNAME=" then the settings in the appropriate freetds.conf server are used
  • If your connection string uses "DSN=" then the settings in the appropriate odbc.ini DSN are used

odbcinst.ini is a red herring. FreeTDS never checks that for settings.

The settings you specify in the connection string are always respected. It also always respects the environment variables like TDSVER.