BUG: based on grpc, a service can only have one ephemeral instance.

[caqhy]

Describe the bug
Based on http, a service can have multiple ephemeral instances.
Based on grpc, a service can only have one ephemeral instance. When different ephemeral instances are registered multiple times in a service, these ephemeral instances will be overwritten. Is this a bug?

Expected behavior
When registering based on grpc, a service can have multiple ephemeral instances.

Actually behavior
When registering based on grpc, the ephemeral instance disappears.

How to Reproduce
Steps to reproduce the behavior:

1. Use nacos-client version 2.x
2. Register multiple ephemeral instances using the client

Desktop (please complete the following information):

• OS: [Windows]
• Version [nacos-server latest master, nacos-client 2.x]
• Module [naming]
• SDK [original]

[chenhao26-nineteen]

Due to certain changes in the registration mechanism of Nacos 2.0, the same client can only register one temporary instance for the same service. However, the batch registration feature of temporary instances is supported in 2.1.1. Please use com.alibaba.nacos.client.naming NacosNamingService # batchRegisterInstance Registers Multiple Instances

[caqhy]

@chenhao26-nineteen
Since NacosNamingService # batchRegisterInstance allows the same client to register multiple ephemeral instances, how about letting NacosNamingService # registerInstance also allow the same client to register multiple ephemeral instances?

[chenhao26-nineteen]

refer #5863

[caqhy]

refer #5863

OK, I've seen discussions about issue #5863. But I found out that NacosNamingService#registerInstance allows the same client to register multiple persistent instances, is this correct?

[chenhao26-nineteen]

yes