Upgrade from 3.0 to 3.1

Function Modification Points

1. Nacos Group Alignment (Application-level Service Discovery)

In Dubbo 2.7.x, the group value configured in the Nacos Registry URL aligns with the group grouping in the Nacos Registry. (group can be considered similar to a namespace for soft isolation)

In Dubbo 3.0.x, the group configured in the Nacos Registry URL is not used by default, and DEFAULT_GROUP is used instead. (group no longer provides isolation functionality)

In Dubbo 3.1.x, the group value configured in the Nacos Registry URL will be realigned with the group grouping in the Nacos Registry.

Notes:

1. Please check if the group attribute is configured in the registry URL, and if so, ensure that the group values for both the server and the consumer are consistent. If they are not, please modify them to be consistent.
2. If you do not want the group to be realigned with the group grouping in the Nacos Registry, you can configure the global property value dubbo.nacos-service-discovery.use-default-group=false to ignore this feature.