@二村 真由 ,
Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
The Azure website you shared shows the list of images supported by Azure that are valid and supported by RedHat. I am attaching the list of Redhat images supported by Azure. So, you can't build 7.1 from the Azure portal. If you have an existing RedHat 7.1 version VM,
Can you please check if it works if you upload your own virtual image and create a VM on Azure? for more information, please read the article - https://learn.microsoft.com/en-us/azure/virtual-machines/linux/redhat-create-upload-vhd.
Hope I answered your question. Thanks.
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