Debugging Interactive Apps
Log location
App completes without being able to connect to it.
If your application goes from queued to starting to completed without
ever allowing you to connect to it, the application failed to start correctly.
First, review the output for that session. You're likely to see some errors there.
Empty Variables in submit.yml.erb
Previous versions of Open OnDemand threw errors when attempting to use undefined
variables in the submit.yml.erb. Undefined variables are evaluated as nil.
This being the case, you may be debugging an issue where a particular value that should
be there is missing or zero. Casting a nil to a string returns an empty string and
casting nil to an integer returns zero.
For example you may see an error like this if you're trying to use a variable
to supply --ntasks-per-node to Slurm's sbatch command.
In debugging a situation like this, it may be helpful to raise an error displaying all the variables that are available.
<%# submit.yml.erb %>
<%-
# ... ruby code ...
raise(StandardError, to_h.inspect)
-%>
It is most likely that the variable in question is in fact missing
or misspelled in either the form.yml or submit.yml files.