backup and restore all MySQL

#backup all databases in one file (eventually add the option --add-locks):
mysqldump -u username -p -–all-databases > file.sql

#backup all databases in one gzipped file:
mysqldump -u username -p -–all-databases | gzip > file.sql.gz

#restore all databases:
mysql -u username -p < file.sql 

#single database

mysqldump database_name > database_name.sql

#Multiple databases can be backed up at the same time:
mysqldump --databases database_one database_two > two_databases.sql

https://snipt.net/danfreak/backup-and-restore-all-mysql-databases-with-2-simple-commands/