AWS Elastic Beanstalk Swap Environment Urls
byAWS provides a feature to exchange or swap the CNAME between environments. Documentation says -
CNAME swap
Because AWS Elastic Beanstalk performs an in-place update when you update your application versions, your application can become unavailable to users for a short period of time. You can avoid this downtime by performing a blue/green deployment, where you deploy the new version to a separate environment, and then swap CNAMEs of the two environments to redirect traffic to the new version instantly. A blue/green deployment is also required when you want to update an environment to an incompatible platform version.If I want to upgrade my elastic beanstalk platform from say - for example php 5.6 to php 7.1 - then unfortunately I cannot do it. It allows me to upgrade within 5.6 platform but not switch between major platforms. Only recommended way is to create new environment with major upgraded platform and then swap the environment urls. This way original environment url will still be pointed to my domain running new platform.

