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a

Aniruddha Sengupta

03/07/2022, 2:27 PM
Hello all Hope that you are well. I have a flow which runs a series of shell commands but the first command is to make a Singularity image with the command
make_shell
. This command does not return any exit codes, so when I tried to run it as a standalone task, my server crashed. What would be the best way to ensure that this command is passed off first before executing other shell tasks? Thanks,
k

Kevin Kho

03/07/2022, 2:29 PM
Hi @Aniruddha Sengupta, not quite getting. You have a ShellTask that has no exit code? And it crashes the entire Prefect server?
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Aniruddha Sengupta

03/07/2022, 2:32 PM
Hi Kevin, yes so essentially I have a bash script which I have converted to ShellTasks but the very first line in the original script is
make_shell
. I do not think this command returns an exit code, it just creates an environment to perform tasks (a bit like activating a Python virtual environment). So I was just wondering what would be the best way to tackle this. Does this make sense?
k

Kevin Kho

03/07/2022, 2:49 PM
I think it does. I can confused if it crashes the Flow or the entire Server?
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Aniruddha Sengupta

03/07/2022, 3:03 PM
The server which runs inside a virtual machine
k

Kevin Kho

03/07/2022, 3:05 PM
Does it only happen when running inside a Flow? Or does
make_shell
also kill the Server if you run in independently?
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Aniruddha Sengupta

03/07/2022, 3:06 PM
It only happens inside a Flow, inside a terminal ithin the virtual machine takes about two seconds. And the Flow is configured to be a LocalRun inside the same virtual machine.
k

Kevin Kho

03/07/2022, 3:08 PM
Pretty confused why that would crash the server if running it outside does not. You have to restart the server when this happens with
prefect server start
?
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Aniruddha Sengupta

03/07/2022, 5:44 PM
Hey Kevin So it turns out I was being stupid and the Prefect task was failing because the command had already been run. So it was an error on my end. My apologies for this.
k

Kevin Kho

03/07/2022, 5:45 PM
Ah ok no worries! Glad you figured it out