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Azure IoT
A category of Azure services for internet of things devices.
402 questions
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John Wong Yek Hon Greetings!
Please see below answers to your queries.
Refer to the Azure document https://learn.microsoft.com/en-us/azure/iot-hub/iot-hub-ha-dr#microsoft-initiated-failover For Microsoft-initiated failover, the RTO is about 2-26 hours. I would like to clarify the RTO here means when the primary region is down, it will auto failover soon enough to the secondary region?
Your understanding is correct. When the primary region experiences a failure, Microsoft initiates a failover to the secondary region. The RTO indicates the estimated time it takes to switch over to the secondary region.
Microsoft-initiated failover is exercised by Microsoft in rare situations to fail over all the IoT hubs from an affected region to the corresponding geo-paired region. This process is a default option and requires no intervention from the user.
The 2-26 hours here refer to the expected time to auto failback to the primary region? or does it means it will take at least 2 hours to failover to the secondary region, which means my solution will be totally unavailable (not performance degradation) during that time?
The RTO (Recovery Time Objective) of 2-26 hours for a Microsoft-initiated failover refers to the time it takes for Microsoft to complete the failover process from the primary region to the secondary region when the primary region is down.
Our solution is now deployed in West Europe, and we are about to introduce a new feature that requires the IoT Hub. However refer to your document https://learn.microsoft.com/en-us/azure/iot-hub/iot-hub-ha-dr#availability-zones, the West Europe currently doesn't support Data Resiliency yet. May I clarify does it means no zone-redundancy yet, for the IoT Hub service in West Europe? Any expected timeline for how soon the data resiliency will be available in WE? Is it advisable to deploy the IoT Hub into the paired North Europe, while my other services in the WE (so they will communicate across these 2 regions)? And once the data resiliency is ready in WE later, is there a way to move the IoT Hub back to WE, and what about the downtime?
Yes, you are correct that West Europe currently does not support Data Resiliency for IoT Hub.
This means that zone-redundancy (the ability to automatically replicate data across different availability zones within the same region) is not available for IoT Hub in West Europe.
There is no specific timeline for when data resiliency will be available in West Europe. I would suggest you, please keep an eye on the Azure Updates page for product updates, roadmap, and announcements.
Please note that, it is feasible to deploy the IoT Hub in North Europe while keeping other services in West Europe. However, the communication between your IoT Hub and other services would happen across regions, which could introduce latency and potential data transfer costs.
I would suggest you, please check How to clone an Azure IoT Hub to another region
Regarding downtime while moving, The exact amount of downtime would depend on your setup and the data.
I hope this address your queries. Do let me know if you have any further queries.