Hello Istvan Fazakas,
Thanks for your question.
SSH to individual containers within a multi-container Azure App Service is not natively supported. You can try from ssh support on your docker image.
You must add SSH support to your Docker image by adding an 'sshd_config' file to your repository, which configures OpenSSH and must include the items that were explained here.
Also see: Enabling SSH on Linux Web App for Containers
Regards,
Abiola
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