Hello @Chao Yan ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you would like to know more about the impacts of the Azure Basic Load Balancer retirement.
If we delete the old Basic Load Balancer and create a same one by arm template, it will fail after 31 March 2025, right?
If you delete the old Basic Load balancer and create a same one before 31st March 2025, it will not fail. You can still create new Basic SKU load balancers till 31st March 2025. But you'll no longer be able to deploy new ones after 31 March 2025. So, yes, the new deployments will fail after 31 March 2025.
If we don't delete the old Basic Load Balancer and only update it by arm template, it will still work after 31 March 2025, right?
Yes, it will work after 31 March 2025 but only till 30 September 2025. Post 30 September 2025, the existing Basic SKU load balancer will stop working, as it will be retired.
To avoid any potential service disruptions, review pricing and then follow the detailed steps to upgrade from Basic Load Balancer to Standard Load Balancer by 30 September 2025.
Kindly let us know if the above helps or you need further assistance on this issue.
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