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Hi, (1.0) we're seeing some strange behavior with ...
# ask-community
b
Hi, (1.0) we're seeing some strange behavior with child flows. When a new version of a long running parent flow (e.g. a backfiller) is registered with prefect cloud, some child flows kicked off with 
prefect.tasks.prefect.create_flow_run
are being canceled without any additional info in the logs. Is this expected? Has anyone else encountered similar behavior?
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b
Hi Brian, just for clarification, is the new version of the parent flow being registered while an older version is still running?
Also would you mind sending over a few examples of the flow runs which are being cancelled?
b
Yes I think both the parent and child flow are having new versions registered while the parent is running and multiple instances of the child are running. Here is an example ID 
2f4d6f6f-9a9a-43cc-a487-ac2f772b8363
b
Thank you for sending over the ID. After looking at the state change information for that run, I can see that it was Cancelled with the following message: 
Flow 0125ceac-842a-43f8-ae1b-e96ae55900e4 was archived.
The only states that I'm seeing for this particular run are 
Scheduled
and 
Cancelled
. When a new version of a flow is registered, the previous version is archived to ensure that only one version of the flow is active. This would cause any deprecated child flows which are `Scheduled`to be 
Cancelled
.
If you want to avoid this going forward, changing the name of the flow (even by one character) at the point of registration should create a new flow group that isn't linked to the existing flow.
b
Thanks for the info Bianca, that's very helpful
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