Backup – How to Automatically Archive a Directory

backup

I want to do one way synchronization.

I am having Folder A on my computer which is constantly updated with content.
Another Folder B is used for backup purpose which is on external HDD.

Now what I expect is that whatever extra which is present in folder A should go to folder B. However something which is present in B and NOT in A ""shall NOT be copied to A"".

In a nutshell, the backup folder may copy everything from the source folder, however nothing should be copied form backup folder to the source.

Best Answer

Sounds like a perfect task for rsync

sudo rsync -az /path_to/A /path_to/B

-a archive mode (implies recursive, copy symlinks as symlinks, preserve owner, modification times, group, owner, special and device files)

-z compresses the data

If you wish to remove files deleted in A from files in B, use the --delete option

For additional information see:

https://help.ubuntu.com/community/rsync

You can run rsync from cron

sudo crontab -e

Add in an hourly task

@hourly rsync /path_to/A /path_to/B

https://help.ubuntu.com/community/CronHowto

Related Solutions

Ubuntu – How to efficiently copy only modified files from a disk to external usb

You're sort of describing what rsync was designed for. From man rsync:

   Rsync  finds  files  that  need to be transferred using a "quick
   check" algorithm (by default) that looks  for  files  that  have
   changed  in  size  or in last-modified time.  Any changes in the
   other preserved attributes (as requested by options) are made on
   the  destination  file  directly  when the quick check indicates
   that the file’s data does not need to be updated.

There's also a lot of guff about networking, but it's happy doing local too.
Essentially all you need is:

rsync -rtv /home/my_projects_linux /mounted_drive/my_projects_linux

There are a ton of options available but -rtv will sync recursively, keeping the timecodes the same, while being verbose about what it's doing.

Best Answer

Related Solutions

Ubuntu – How to efficiently copy only modified files from a disk to external usb

Related Question