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What is the duration / downtime required for the migration as we need to take downtime approval from client accordingly?
The upgrade normally takes a few minutes for the script to finish. The following factors may lead to longer upgrade times:
- Complexity of your load balancer configuration
- Number of backend pool members
- Instance count of associated Virtual Machine Scale Sets or Virtual Machines
Keep the downtime in mind and plan for failover if necessary.
In case of any issue occurred during migration, what are the rollback plans which we can perform?
Here is the few issue What happens if my upgrade fails mid-migration?
- What are the prerequisites which we can take care off before performing the migration?
- What are the post migration actions for us to be taken?
Refer this link: Pre- and Post-migration Steps
What will be the impact of the migration on the applications?
Yes, because the Basic Load Balancer needs to be removed before the new Standard Load Balancer can be created, there will be downtime to your application.
Refer this link for details:
Upgrade from Basic to Standard with PowerShell - Azure Load Balancer | Microsoft Learn
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