Backup only changed files in data dir?

Hi.

I have a NCP and a 500mb drive. I have a 2TB drive as backup and to backup data takes long time.

Is it posible to backup only changed files as most of them are not changed every week?
Some mirroring backup without raid? To local usb hdd?

Thanx

You can e.g. use “rsync” with the option “–link-dest”.

--link-dest=DIR hardlink to files in DIR when unchanged
https://linux.die.net/man/1/rsync

There are also tools with incremental backups like “rsnapshot” with same or similar functions.

https://packages.debian.org/rsnapshot
https://packages.ubuntu.com/rsnapshot

apt-get install rsnapshot

You must use the same or similar file-system-types like EXT4.

Thank you.

So. Im new to Linux so.
If I want to sync data from /media/drive1/ncdata/ to backup disc /media/drive2/backup/ what command should I use?

I only want to sync data. I take regulary snapshots and backup without data.

I think it is not to easy. You should test it on a test system.
Another possibility is a tool like “rsnapshot” with a config file.

Read
https://www.pontikis.net/blog/howto-rsnapshot-backup