service-discovery

我们鼓励使用英文，如果不能直接使用，可以使用翻译软件，您仍旧可以保留中文原文。
We recommend using English. If you are non-native English speaker, you can use the translation software.

Which Component
eg. Nacos Discovery, Sentinel

Is your feature request related to a problem? Please describe.
Feign限流降级好像只支持url粒度，能否支持服务粒度，就像对RestTemplate支持两种粒度一样(Feign's current limiting degradation seems to only support URL granularit

Both versions of nacos2.0.0 and nacos2.0.2 were tried, unable to cluster successfully under mac and centos, the log output service is being restarted, unable to start normally, and cannot complete the election.
尝试了nacos2.0.0和nacos2.0.2两个版本，在mac和centos下都无法集群成功，日志一直输出服务在重启，无法正常启动，也无法完成选举.

Right now, whenever Zenmap crashes, it gives the user a stack trace and asks the user to send it to the Nmap dev list. So we get a flood of emails (most of which aren't even allowed through moderation) which often contain just a stack trace with no subject line or any explanatory text in the message body. Lots of these are for well known issues in older versions of Zenmap. So it's not very usef

If not for some particular exceptions, the status code returned from our WebAPI on error is always 500, regardless of the kind of error.

If an object already exists, for example, it should be returned as 409. If the object does not pass the schema validation, it should be a 415.

Go through the whole WebAPI and verify that the status codes are being returned correctly.

Hint: Error cl

Describe the bug

A clear and concise description of the bug.
when my asp.net core 3.1 app host in IIS, the url console is 127.0.0.1，so，when i have Multiple instances，the instances name will be the same,such as 127.0.0.1:svaname:port，eureka server think they are a single instance.
i print the console in source code：
![image](https://user-images.githubusercontent.com/6300834/101754289-8ad92

Add a sample that shows how to add a custom endpoint using the management endpoints library.