Installation and tuning of Open Link Virtuoso on Ubuntu

OpenLink Virtuoso is the first CROSS PLATFORM Universal Server to implement Web, File, and Database server functionality alongside Native XML Storage, and Universal Data Access Middleware, as a single server solution. OpenLink Virtuoso plays a vital role for semantic web programming, it can work as a solid SPARQL end point, which can be supported by almost all endpoint interfaces. There are following steps to install and start OpenLink Virtuoso universal server-

1. Install Dependencies

To install OpenLink Virtuoso first of all following dependencies are needed-

  • autoconf    2.57    http://www.gnu.org/software/autoconf/
  • automake    1.9    http://www.gnu.org/software/automake/
  • libtool    1.5.16    http://www.gnu.org/software/libtool/
  • flex    2.5.33    http://www.gnu.org/software/non-gnu/flex/
  • bison    2.3    http://www.gnu.org/software/bison/
  • gperf    2.7.2    http://www.gnu.org/software/gperf/
  • gawk    3.1.1    http://www.gnu.org/software/gawk/
  • m4    1.4.1    http://www.gnu.org/software/m4/
  • make    3.79.1    http://www.gnu.org/software/make/
  • OpenSSL    0.9.7i    http://www.openssl.org/
  • First of all check all the dependencies whether installed or not. (Version is important!)To check the version use following sequence.#autoconf –version
    # automake –version
    #libtoolize –version
    #flex –version
    #bison –version
    #gperf –version
    #gawk –version
    #m4 –version
    #make –version
    #openssl version
    During checking of the dependencies you will know whether they are installed or not and if not installed, for example,  you will get  something like-
    The program ‘autoconf’ is currently not installed.  You can install it by typing:apt-get install autoconf
    Then why should you wait!! install the packages using “apt-get” one by one in the sequence as checking the version.
    OR
    you can install these from synaptic package manager.
    2. run this command  apt-get install libssl-dev from your terminal
    3. Download OpenLink Virtuoso from source forge (Link)
    4. Extract the package in any directory.
    5. Go to the directory where you have extracted the package.
    6. It is better to run autogen.sh by typing ./autogen.sh, which checks for the presence and right version of some of the required components, and if it reports any missing package then install that package.
    7. Set following  environmental variable by typing (one by one) –
    CFLAGS=”-O3″
    export CFLAGS
    8. type  `./configure CFLAGS=”-O3″’  to configure the package for your system.
    Note: It should be “-O3”, not “-03” (big O, not zero), otherwise gcc won’t recognize the flag
    Sometimes, the system generates this error after running the ./ configure command. checking validity of the OpenSSL headers in /usr… configure: error: bad. Check config.log for details. To Resolve this, you have to install libssl-dev in your. Run the following command to install libssl-dev and again run the ./configure.
    sudo apt-get install libssl-dev
    9. Type `make’ to compile the package.
    10. Type `make install’ to install the programs and any data files and documentation.
    To start the server you have two steps-
    1. Go to
    ‘cd  /usr/local/virtuoso-opensource/var/lib/virtuoso/db’
    then type ‘/usr/local/virtuoso-opensource/bin/virtuoso-t -f &’
    Finally use the server from your browser by typing ‘http://localhost:8890/’ in the address bar.
    Use the powerful multipurpose opensource server !!
    Note:- All documentations are available at Wiki Page of  OpenLink Virtuoso.
    To grant the SPARQL to update and insert data into a graph-
    1. Go to “http://localhost:8890/conductor” and login as “dba” (Uname and Pass =” dba”)
    2. Click on “Interactive SQL (ISQL)”.
    3. In ISQL window type the command GRANT ALL PRIVILEGES TO “SPARQL”;
    To access to the virtuoso.ini file configuration and tuning:
    sudo gedit /usr/local/virtuoso-opensource/var/lib/virtuoso/db/virtuoso.ini
    To access to the isql through command line:
    Go to cd /usr/local/virtuoso-opensource/bin/
    / and then run ./isql 1111 <user> <pwd>
    By default, virtuoso sets the ‘dba’ as  user name and passwor

Remove a graph from virtuoso

To remove a graph from virtuoso, open isql through command line and then run the following command.


log_enable(3,1);
DELETE FROM rdf_quad WHERE g = iri_to_id ('http://mygraph.org');

Change Password of Virtuso dba and dev

One database user and 2 WebDAV users. These users have their passwords set to default values. It is therefore important to change them immediately after the installation.The one database user is the database administrator with username “dba” and password “dba”. This can be changed using the Interactive SQL utility. When started without parameters, the ISQL tries to log on as dba with the default password. The SQL statement to change a user’s password is:

 set password <old password> <new password>

The password is an identifier, so take care to use proper quotation.

You can also use the graphical Virtuoso Administration Interface to administer Virtuoso database users.The 2 WebDAV user accounts, dav and davuser also have their password set to their username. There are 2 easy ways to change them. Either use the GUI in Administration Interface under WebDAV Administration / WebDAV services / Users Administrator or use the SQL statement:

 update WS.WS.SYS_DAV_USER set U_PASSWORD='<new password>'
where U_NAME='<username>'

Note quotation around varchar values. Please remember to perform these operations for all Virtuoso server instances installed. By default these are the Virtuoso with an empty database and Virtuoso [demo] with the demo database.

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