[CentOS] Copying a live system

Tue May 3 14:33:32 UTC 2016
Leon Fauster <leonfauster at googlemail.com>

Am 03.05.2016 um 15:55 schrieb Timothy Murphy <gayleard at eircom.net>:
> I want to backup my current CentOS-7.2 system to another drive.
> Is it safe to copy the system while it is running?
> Eg by
> mount /dev/sdb5 /mnt
> rsync -HPaxvz /. /mnt/
> I've found contradictory advice on the web.

It depends, the running services should answer ... for a mysqld running system:

Delete the -x option above and add

--exclude /proc --exclude /sys --exclude /mnt --exclude /var/lib/mysql  

and then 

mysqldump --add-drop-table -c --create-options -x -u root -p -A > mysqldump-$(date +%s).sql

for example ...