1. Check the error log for the MySQL 1801 error:
$ tail -f /var/log/mysql/error.log
2. Check the MySQL configuration file for any misconfigurations:
$ cat /etc/mysql/my.cnf
3. Check the MySQL process list to see if there are any processes that are running that shouldn't be:
$ mysqladmin -u root -p processlist
4. Check the MySQL user table to see if there are any users that shouldn't have access:
$ mysql -u root -p -e "SELECT User, Host FROM mysql.user;"
5. Check the MySQL grant tables to see if there are any grants that shouldn't be in place:
$ mysql -u root -p -e "SELECT * FROM mysql.db;"
6. Check the MySQL system variables to see if there are any variables that are set incorrectly:
$ mysql -u root -p -e "SHOW VARIABLES;"
7. Check the MySQL status variables to see if there are any variables that are set incorrectly:
$ mysql -u root -p -e "SHOW STATUS;"
8. Once the issue has been identified and fixed, restart the MySQL server:
$ service mysql restart
9. Finally, it is recommended to use an automated database observability tool to monitor and fix the MySQL 1801 in question. This tool can provide real-time insights into the performance and health of the database, as well as alerting when issues arise. This can help to quickly identify and fix any issues that may arise in the future.