Hello @Malcolm ,
I checked with the Azure Bastion product group and they mentioned that connectivity to classic VM via Azure Bastion is not supported and we don’t have plans to support it in future either.
Also, JIT is not supported for classic VMs.
Reference : https://zcusa.951200.xyz/en-us/azure/security-center/just-in-time-access-usage?tabs=jit-config-asc%2Cjit-request-asc#availability
So, it would be best to migrate the VMs to ARM for Azure Bastion support.
Kindly let us know if the above helps or you need further assistance on this issue.
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