My understanding is that you are using the Run Command in AKS to attempt to run Linux commands. This is not the intended functionality of Run Command for AKS. It is intended to run kubectl and helm commands on your cluster. You can use the commands listed here.
If you want to run commands on the cluster nodes you can Connect using kubectl debug. Please check to see if this option works for you. If you have more questions please let me know and I will do my best to assist.
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