I back up all databases with a scheduled task, and I do this at night, but once the process starts, I can't access the sites until the backup is complete.
Locking of the site while the database is being backed up.
Hello, backing up the database requires a lot of disk io. It is recommended that you back up the server when it is idle.
Can I access other services besides the website? ssh aapanel etc.
a month later
You can perform a backup using a command like the one below, which will ensure it is done with lower priority on the disk. This way, the sites may not become unresponsive, or you can use Percona XtraBackup for backup, which will not affect the operation of the sites. I will try both and update you.
ionice -c2 -n7 mysqldump -u your_username -p your_database_name > backup.sql