Merge pull request #75467 from SyntaxC4-MSFT/jj-patch1

Hotfix for VMs

Author: SyntaxC4

includes/virtual-machines-common-planned-maintenance.md

@@ -30,7 +30,18 @@ These non-rebootful maintenance operations are applied fault domain by fault dom
 
 Some applications may be impacted by these types of updates. In case the VM is live migrated to a different host, some sensitive workloads might notice a slight performance degradation in the few minutes leading up to the VM pause. Such applications can benefit from using Scheduled Events for [Windows](../articles/virtual-machines/windows/scheduled-events.md) or [Linux](../articles/virtual-machines/linux/scheduled-events.md) to prepare for VM maintenance and have no impact during Azure maintenance. Azure is also working on maintenance control features for such ultra-sensitive applications. 
 
-95% of Azure fleet supports memory preserving updates and live migration. The exceptions are M, L, H, and N series VMs.  
+## Live migration
+
+Live Migration is a non-rebootful operation that preserves memory for the VM and results in a limited pause or freeze, typically lasting no more than 5 seconds. Today, all Infrastructure as a Service (IaaS) Virtual Machines, apart from G, M, N, and H series, are eligible for Live Migration. This equates to over 90% of the IaaS VMs deployed to the Azure Fleet. 
+
+Live Migration is initiated by the Azure Fabric in the following scenarios:
+- Planned Maintenance
+- Hardware Failure
+- Allocation Optimizations
+
+Live Migration is leveraged in some planned maintenance scenarios, and Scheduled Events can be used to know in advance when Live migration operations start.
+
+Live Migration is also used to move Virtual Machines off of hardware with an impending predicted failure when detected by our Machine Learning algorithms and to optimize Virtual Machine allocations. To learn more about our Predictive Modeling that detects instances of degraded hardware, please see our blog post entitled [Improving Azure Virtual Machine resiliency with predictive ML and live migration](https://azure.microsoft.com/blog/improving-azure-virtual-machine-resiliency-with-predictive-ml-and-live-migration/?WT.mc_id=thomasmaurer-blog-thmaure). Customers will always receive a Live Migration notice in their Azure portal in the Monitor / Service Health Logs, as well as through Scheduled Events if these are being used.
 
 ## Maintenance requiring a reboot
 
@@ -46,11 +57,11 @@ When the self-service window has passed, the **scheduled maintenance window** be
 
 For information on managing maintenance requiring a reboot, see "Handling planned maintenance notifications" for [Linux](../articles/virtual-machines/linux/maintenance-notifications.md) or [Windows](../articles/virtual-machines/windows/maintenance-notifications.md). 
 
-### Availability Considerations during Scheduled Maintenance 
+### Availability considerations during scheduled maintenance 
 
 If you decide to wait until the scheduled maintenance window, there are a few things to consider for maintaining the highest availability of your VMs. 
 
-#### Paired Regions
+#### Paired regions
 
 Each Azure region is paired with another region within the same geography and together they make a regional pair. In scheduled maintenance phase, Azure will only update the VMs in a single region of a region pair. For example, when updating the VM in North Central US, Azure won't update any VM in South Central US at the same time. However, other regions such as North Europe can be under maintenance at the same time as East US. Understanding how region pairs work can help you better distribute your VMs across regions. For more information, see [Azure region pairs](https://docs.microsoft.com/azure/best-practices-availability-paired-regions).