Get the latest stable release of FreeTDS and install it.

cd /root
wget ftp://ftp.freetds.org/pub/freetds/stable/freetds-patched.tar.gz
tar -zxvf freetds-patched.tar.gz
cd freetds...
./configure --prefix=/usr/local/freetds
make
make install

Now we should tell Direct Admin’s custom build that we want the MS Sql libraries installed using freetds. Edit custom configure php file and add:

--with-mssql=/usr/local/freetds \

Rebuild php:

cd /usr/local/directadmin/custombuild
./build clean
./build php d

Check if modulele is installed:

php -m | grep mssql
mssql