TroubleShooting_Too many Connections

✅ 500 Error on frontend

Although everything was running just fine on postman, when connecting with frontend, there was a 500 error.

🔵 Check Max connections, wait_timeout

Go into Ubuntu then,

mysql -h drugstoredb.cn000owqib3s.ap-northeast-2.rds.amazonaws.com -u root -p

show variables like "%max_connections%";

show status like "%connect%";

show status like '%thread%';

show variables like '%timeout%';

나의 경우 다음과 같은 수치가 나왔다.

• Cache Miss Rate= 2.40%
• Connection Miss Rate= 17%
• Connection Usage= 53%

따라서

• wait_timeout = 180
• max_connections = 300 으로 설정하기로 하였다.

🔵 Change connections, timeout

✔️ AWS parameter

RDS의 parameter 바꿔주기 https://cha-vi.tistory.com/56

설정 이후 show variables like "%max_connections%"; 해보면 내가 바꾼 숫자로 잘 나오는 것 확인 가능

✔️ ubuntu mariaDB

1. Install mariaDB service

sudo apt update
sudo apt install mariadb-server

sudo systemctl start mariadb.service

1. Change config file

cd /etc/mysql/mariadb.conf.d/
sudo nano 50-server.cnf

[mysqld]
max_connections = 300
wait_timeout = 180

1. Restart mariaDB server

sudo systemctl restart mariadb.service

💡 참고자료

• ubuntu, DB 연결 계산 방법 https://velog.io/@kimjiwonpg98/mysql-too-many-connections-error-%ED%95%B4%EA%B2%B0-%EB%B0%A9%EB%B2%95

🔵 Check server.log

지긋지긋하던 too many connections가 사라졌다! 그리고 여러명이 동시에 접속해도 잘 작동한다.