Activating the LDM Installation


  1. Become the LDM user in their home directory.
  2. If the home directory isn't the LDM installation directory (which is unusual) then go to the LDM installation directory:
    $ cd $LDMHOME
  3. If an LDM is running, then stop it:
    $ ldmadmin stop
  4. If the runtime symbolic link exists, then remove it:
    $ rm runtime
  5. Create the runtime symbolic link to the just-installed LDM:
    $ ln -s $VERSIONDIR runtime
    where $VERSIONDIR is the version-dependent directory of the LDM.
  6. Ensure that a valid product-queue exists by doing one of the following:
    1. If the product-queue doesn't exist, then create it with the following command:
      $ ldmadmin mkqueue -f
      where the -f option is for "fast" creation of the product-queue and assumes that sufficient space exists on the disk.
    2. If the product-queue exists and the command
      $ pqcheck -v
      indicates that it doesn't have a writer-counter, then create the counter and set it to zero with the following command:
      $ pqcheck -F
  7. Start the LDM:
    $ ldmadmin start
  8. Verify that the LDM is working:
    $ ldmadmin watch
    How quickly this verifies your LDM depends on the rate at which data-products are inserted into the product-queue.

If the LDM system is already running, then you can minimize the time that the LDM is off-line by combining some of the above steps. For example 

$ cd $LDMHOME && ldmadmin stop && rm -f runtime && \
ln -s $VERSIONDIR runtime && ldmadmin start && ldmadmin watch
Where $VERSIONDIR is the version-dependent directory of the LDM.

If you encounter a problem, check the LDM logfile for relevant messages.