@artsiom korbut There was an outage on Jan 21st, which would have led to this issue with Cloud Shell on Azure Portal. Please try Cloud Shell on Azure Portal again, now that the issue is mitigated.
https://azure.status.microsoft/en-us/status/history/
Summary of Impact: Between 01:57 UTC and 08:58 UTC on 21 January 2024, customers who leverage Azure Resource Manager (ARM) may have experienced issues when performing resource management operations. This impacted users of Azure CLI, Azure PowerShell, the Azure portal, as well as Azure services that depended upon ARM for their internal resource management operations.
Preliminary Root Cause: A backend service made a configuration change that caused ARM web roles to crash.
Mitigation: We mitigated impact by bypassing the configuration change which allowed the ARM web roles to return to a healthy status.
Next Steps: We will follow up in 3 days with a preliminary Post Incident Report (PIR), which will cover the initial root cause and repair items. We'll follow that up 14 days later with a final PIR where we will share a deep dive into the incident.
Additional reading: https://learn.microsoft.com/en-us/answers/questions/1503162/cloud-shell-will-not-register-and-or-start
If you are still seeing this issue, let me know in the comments and I will look into it.
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