| Issue description | 
|---|
| How to troubleshoot it | 
| How to fix it | 
| Cannot connect to database | 
|---|
| Check if mysqld is running and if the ports are available on the localhost and from the host you try to connect from. | 
| Check load on database server using top | 
| Check the ports using nmap -Pn localhost | 
| Check the ports from remote using nmap -Pn databasehost | 
| Check the logging less /var/log/mysql.log | 
| Try to login locally on the database server mysql -u root -p | 
| Fixing (you might kill your webserver/application first) | 
| Restart mysql service service mysqld restart | 
