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Figure 4 shows a single public shared ALB that is pointing to two different stack 101 & 102. Both stacks are configured with the same path information. When the ABL ALB encounters duplicate paths that for the same request, it will send all traffic to the path with the lowest priority. Therefore, all traffic as depicted in Figure 4, will continue to go to portaportal-prod-101 (since it has a lower priority). To promote 102 to be the new production, the ALB must be changed to assign 102 a lower priority than 101. At that point all new traffic will go to stack 102.
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