Activating the LDM Installation


  1. Become the LDM user in their home directory.
  2. If an LDM is running, then stop it:
    ldmadmin stop
  3. If the runtime symbolic link exists, then remove it:
    rm runtime
  4. Create the runtime symbolic link to the just-installed LDM:
    ln -s ldm-6.13.13 runtime
  5. Ensure that a valid product-queue exists by doing one of the following:
    1. If the product-queue doesn't exist and the command
      df -k var
      indicates that sufficient space exists for it, then create the product-queue with the following command:
      ldmadmin mkqueue -f
      where the -f option requests "fast" creation.

      If you don't have sufficient space for the product-queue, then you'll have to free-up some space or configure a smaller queue.

    2. If the product-queue exists, then execute the command
      pqcheck -v
      and do one of the following:
      1. If the product-queue is invalid, then recreate it with the following commands:
        ldmadmin delqueue
        ldmadmin mkqueue -f
      2. If the product-queue doesn't have a writer-counter, then create the counter and set it to zero with the following command:
        pqcheck -F
  6. Start the LDM:
    ldmadmin start
  7. 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 $HOME && ldmadmin stop && rm -f runtime && \
ln -s ldm-6.13.13 runtime && ldmadmin start && ldmadmin watch

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