How to write good support requests

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... written by and from the perspective of HPC administrators.

Writing good support requests is not only good for the support team, it is also better for you! Due to the administrator teams having lots of help requests, the time to understand each problem is at a premium. The easier it is to understand yours, the faster we will get to it.

Below is a list of good practices.

Never send support requests to staff members directly

Always send them to the proper team or ticket system mailing address, and staff members will pick them up there. Some staff members may work on the support line only part time. Sending the request to the main address makes sure that somebody will pick it up.

Do not manhandle us as simple “Let me Google that for you” assistants

Seriously: have you searched the internet with the exact error message and the name of your application…? Other scientists may have had the very same problem and might have been successful in solving it. By the way: that’s almost always how we start to research, too…

Give descriptive subject

Your subject line should be descriptive. “Problem on Cluster” is not a good subject line since it could be valid for basically every support email we get. The support staff is a team. The subjects are the first thing that we see. We would like to be able to classify emails according to subjects before even opening the email.

Include actual commands and error messages

We cover this below, but it’s so important it needs to be mentioned at the top, too: include the actual command you run and actual error messages. Copy and paste. If you don’t include this, we will be slightly annoyed and immediately ask for it.

Please, do not screen shoot your ssh terminal and send us pictures (jpg, png, tiff…) of what you saw on your monitor! From these, we would be unable to cut & paste commands or error messages, unnecessarily slowing down our research on your problem. Your sample output does not need at all to “look good”, and we don’t need to know what fancy ssh or terminal software you have: a simple text-based cut & paste directly into the mail or ticket is the best we can work on with.

New problem–new email

Do not send support requests by replying to unrelated issues. Every issue or ticket gets a number and this is the number that you see in the subject line. Replying to unrelated issues means that your email gets filed under the wrong thread and risks being overlooked.

The XY problem

This is a classic problem. Please read http://xyproblem.info. Often we know the solution but sometimes we don’t know the problem.

In short (quoting from http://xyproblem.info):

  • User wants to do X.
  • User doesn’t know how to do X, but thinks they can fumble their way to a solution if they can just manage to do Y.
  • User doesn’t know how to do Y either.
  • User asks for help with Y.
  • Others try to help user with Y, but are confused because Y seems like a strange problem to want to solve.
  • After much interaction and wasted time, it finally becomes clear that the user really wants help with X, and that Y wasn’t even a suitable solution for X.

To avoid the XY problem, if you struggle with Y but really what you are after is X, please also tell us about X. Tell us what you really want to achieve. Solving Y can take a long time. We have had cases where after enormous effort on Y we realized that the user wanted X and that Y was not at all the best way to achieve X.

Tell us also what worked

Rather often we get requests of the type “I cannot get X to run on two nodes”. The request then does not mention whether it worked on one node or on one core or whether it never worked and that this was the first attempt. Perhaps the problem has even nothing to do with one or two nodes. In order to better isolate the problem and avoid wasting time with many back and forth emails, please tell us what actually worked so far. Tell us what you have tried to isolate the problem. This requires some effort from you but this is what we expect from you.

Specify your environment

Have you or your colleague compiled the code? Which modules were loaded? If you use non-default or self-defined modules and you do not tell us about it, we will waste time when debugging within a different environment.

Simple cases: Be specific, include commands and errors

Whatever you do, don’t say that “X didn’t work”. Exactly give the commands you ran, environment (see above), and output error messages. The actual error messages mean a lot - include all the output, it is easy to copy and paste it (text-only).

The better you describe the problem the less we have to guess and ask.

Sometimes, just seeing the actual error message is enough to give an useful answer. For all but the simplest cases, you will need to make the problem reproducible, which you should always try anyway. See the following points.

Complex cases: Create an example which reproduces the problem

Create an example that ideally we can just copy paste and run to demonstrate the problem. It is otherwise very time consuming if the support team needs to write input files and run scripts based on your possibly incomplete description. See also next point. Make this example available to us. We do not search and read read-protected files without your permission.

Make the example as small and fast as possible

You run a calculation which crashes after running for one week. You are tempted to write to support right away with this example but this is not a good idea. Before you send a support request with this example, first try to reduce it. Possibly and probably the crash can be reproduced with a much smaller example (smaller system size or grid or basis set). It is so much easier to schedule and debug a problem which crashes after few seconds compared to a run which crashes after hours. Of course this requires some effort from you but this is what we expect from you in order to create a useful support request. Often when isolating the problem, the problem and solution crystallize before even writing the support request.


(With kind permission from the author(s) of https://hpc-uit.readthedocs.io/en/latest/help/writing-support-requests.html)