Estoy tratando de ejecutar conectar a un servidor MSSQL desde un servidor web Ubuntu 12.04 con FreeTDS y unixODBC.

Usando tsql puedo conectarme al servidor con

~$ tsql -S dbs3 -U <username> -P <password>

No hay problema allí.

Cuando intento conectarme con isql, aparece el siguiente mensaje de error:

~$ isql -v database3 <username> <password>
[S1000][unixODBC][FreeTDS][SQL Server]Unable to connect to data source
[01000][unixODBC][FreeTDS][SQL Server]Unknown host machine name.
[ISQL]ERROR: Could not SQLConnect

Mis archivos de configuración son los siguientes:

odbc.ini

[database3]
Driver=FreeTDS
TDS_Version=8.0
Servername=dbs3
Port=1433
Database=benchmark_res

odbcinst.ini

[FreeTDS]
Description=FreeTDS v0.91
Driver=/usr/local/lib/libtdsodbc.so
Setup=/usr/local/lib/libtdsS.so
Trace=Yes
TraceFile=/tmp/freetds.log
ForceTrave=Yes
UsageCount=1

freetds.conf

# This file is installed by FreeTDS if no file by the same
# name is found in the installation directory.
#
# For information about the layout of this file and its settings,
# see the freetds.conf manpage "man freetds.conf".

# Global settings are overridden by those in a database
# server specific section
[global]
    # TDS protocol version
;   tds version = 4.2

    # Whether to write a TDSDUMP file for diagnostic purposes
    # (setting this to /tmp is insecure on a multi-user system)
;   dump file = /tmp/freetds.log
;   debug flags = 0xffff

    # Command and connection timeouts
;   timeout = 10
;   connect timeout = 10

    # If you get out-of-memory errors, it may mean that your client
    # is trying to allocate a huge buffer for a TEXT field.
    # Try setting 'text size' to a more reasonable limit
    text size = 64512

# A typical Sybase server
[egServer50]
    host = symachine.domain.com
    port = 5000
    tds version = 5.0

# A typical Microsoft server
[egServer70]
    host = ntmachine.domain.com
    port = 1433
    tds version = 7.0

[dbs3]
    host = <server-ip>
    port = 1433
    tds version = 8.0

Seguí la guía de instalación 1.aquí y 2.aquí

¿Por qué isql no se conecta correctamente?
Supongo que el error es muy obvio, pero soy demasiado estúpido para verlo: D