Azure Batch - Task competes but does nothing

Question

I'm trying to run a task on Azure Batch pool. The task completes with no errors, but produces no output.

I created and configured Ubuntu 18.04 LTS virtual machine, put my .NET Core 2.1 SCA into /usr/local/bin/MyApp and created image from this machine.

Next, i create the batch pool with my custom image and one low-priority node.

When i ssh to it, i can see my application where i put it and can run it as follows:

cd /usr/local/bin/MyApp && ./MyApp some_param

This produces the expected result. But when i create the task in azure portal:

/bin/sh -c cd /usr/local/bin/MyApp && ./MyApp some_param

it runs less then 1s and shows that the task succeeded. But it does not produce any result.

My application simply loads file from blob storage, processes it and uploads back to the blob storage.

When i run the following task in portal:

/bin/sh -c pwd

it outputs:

 /mnt/batch/tasks/workitems/processing-job/job-1/test2/wd

But when i do this:

/bin/sh -c cd .. && pwd

i see nothing in stderr.txt and stdout.txt .

Can it be that it simply can't find my application (and does not throw any errors for some reason)?

I tried adding MyApp to $PATH, but then when i run:

MyApp some_param

in stderr.txt i see access denied error.

I tried executing it under admin and non-admin users with the same result.

Please help.

Answer 1

Cool, so here is the quick answer and hope this caters your need:

• For multiple command failure see this: Azure batch - run multiple commands from command line on linux VM

• ie try this in your command line /bin/bash -c "cd .. && pwd"

• Please also note that the environment variables get populated for known working directory location is in case you are not aware about it already have a look in here: https://docs.microsoft.com/en-us/azure/batch/batch-compute-node-environment-variables and you can use these env vars like $AZ_BATCH_TASK_DIR sample code is there or you can experiment as well.
• https://docs.microsoft.com/en-us/azure/batch/batch-compute-node-environment-variables#command-line-expansion-of-environment-variables