Hi Anuja Vishwanatulawar,
Welcome to the Microsoft Q&A Platform. Thank you for posting your query here.
Based on your query, when migrating the classic to simplified impact and downtime mentioned below
While updating the node communication mode from Classic to Simplified in a Batch Pool advantage is reduces networking complexity by requiring fewer inbound connections and simplifying security configurations. It also improves control over data flow, as no outbound communication to Azure Storage is needed.
For downtime, you need to scale the Batch pool down to zero nodes, migrate to the simplified mode, and then scale it back up. The downtime will vary based on your specific setup but will generally involve some temporary disruption during the scale-down and scale-up processes. Make sure Test the new mode with a small workload first, have a backup and rollback plan. After migration, monitor the system to address any issues quickly
Please refer below document for more information. If you are already familiar with it, that's great.
Use simplified compute node communication
Migrate Azure Batch pools to the simplified compute node communication model
As you ask another query, some of the nodes are marked as N/A. Those pools must be manually updated to the simplified mode before this date.
In case of not updating, the classic compute node communication mode before the date it will be retired. which means batch pools using this mode will stop working properly, leading to service disruptions. Any new features or updates won't be compatible with the classic mode, limiting your ability to take advantage of improvements. The simplified communication model also offers better security, and continuing with the classic mode could leave your pools exposed to vulnerabilities. Additionally, the classic mode requires more complex networking setups, making it harder to manage and maintain compared to the simplified version.
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