{“message”:”Network Error”,”name”:”AxiosError”,”code”:”ERR_NETWORK”,”status”:null}

Above is the error code. I deleted the message part in the middle because the address was exposed.

First of all, the server configuration is (client) react => s3 => cloud front (port 3000),

[Connection to main domain]ex) https://test.com

The node server API is ec2 => node (port 3001).

[EC2 -> Load Balancer -> Router53/subdomain connection] ex) https://sub.test.com

The DB connected to the node server API is rds mysql (t3.micro).

This does not mean that connection is not possible in all cases. There is no problem with the PC, but when using Postman or Naver App/KakaoTalk App, connection is not possible without certain conditions and the above error appears. There is no API error because the connection to the API is not possible and an error occurs in the client.

1. API communication sometimes does not work when accessing the site from the react mobile (Naver/KakaoTalk) app. (status 0)

2. Sometimes it works without specific conditions and sometimes it doesn’t, and there are no problems with PC (except Postman).

3. The maximum DB connection is 60, and direct communication is only possible through API.

4. API communication sometimes does not work when accessing the site from the react mobile (Naver/KakaoTalk) app. (status 0)

5. Sometimes it works without specific conditions and sometimes it doesn’t, and there are no problems with PC (except Postman).

6. The maximum DB connection is 60, and direct communication is only possible through API.