On 09/02/2011 19:53, Roberto Spadim wrote:
i agree with rsync rsync is more filesystem related feature if you want copy files, you should use rsync if you want to copy the device, may be a dd with devices? dd if=/dev/md0 of=/dev/sda if you want a snapshot copy, you should first remount your filesystem to readonly (there´s no flock() for /dev/md0 since filesystem don´t use flock() on /dev/md0) or another way to block writes to filesystem while you is read from device, some filesystems have online backup features.. i don´t know lvm very well, but maybe they implement online backup there... i don´t think it´s a problem to solve at md level (it could work, but the raid1 purpose is make a fail safe device (or partially safe), not a online backup device)
I do both with several of my customers: md array with LVM on top, suspend system services (mailstore), take snapshot, start system services, then rsync diff the snapshot to another drive with luks crypto, which gets rotated off-site once a week. Generally the backup drives are bigger than the system array, so I can keep at least a week's worth of nightlies and several months' worth of weeklies on each one.
Yes, I have my own separate securely-stored copies of their crypto keys. Cheers, John. -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
