Shell Programming and Scripting

Hi all,

I would need a rather simple bash backup script that loops throught the (local) users and for each users backs up (cp!) its /home/username folder.
About the functionalities:

The script has to run every 2 hours (that's cron, so don't mind about that) and the files should be copied to the folder /oldversions/username/date-hh-mm (which have to be created every time)
Also it has to be incremental, only the modified files have to be copied to the folder. Anyways, compression (.tar, etc) is not needed!
The backups should be kept 7 days (168h) -> less important for now

As the permissions of the files&folders have to be kept, I found these lines of code that should copy preserving all this.

Code:

cd /old_dir
find . -depth -print | cpio -pdlmv /new_dir

I'm just finding my way through VBscript but still struggling with this bash scripting jobs. So thanks a lot, in advance, for helping me out!

Regards

At the beginning of the backup process, use the "touch" command to create a file called, say, "timestamp." This file will have a modification time corresponding to when the "touch" command was executed.

Code:

touch timestamp

then, use the -newer switch in the find command of the backup:

Code:

find . -newer timestamp ...

This will find only the files and directories newer than the file "timestamp."

If you're sure no files will be created after commencing the backup, you could execute the "touch" command after the "find" command instead of before it.

Thx, Miller ! That's a good idea for starters. But could you maybe be a little more specific ?
When the script.sh is executed the first time it has to copy everything but at the same time it has to check for this timestamp and if the files are newer only copy those, this for all the next times (from the 2nd you run it)
And preserving the folder's permissions.
Would it be possible demonstrating with a code example of such a script ?

Thanks in advance!

This script creates directories like /oldversions/`date`/user1, /oldversions/`date`/user2, and so on.
If that's not acceptable you have to do much more work......

Create a reference file with the touch command in the /home directory and set the date and time of the file with the last copy date.
If the last copy is from 13 aug 2009 12:00 you can do something like:

Code:

touch -t 200913081200 copy.log

Now your script should looks like (not tested!):

Code:

#!/bin/sh

cd /home

find * -newer /home/copy.log -print | cpio -pvdmu /oldversions/`date`

echo "Last copy on: `date`" >> copy.log

Regards

Thanks a lot Franklin! Only; i get "cpio: Too many arguments" ?
Also, can it be reused, I guess it doesn't compare with a timestamp in the beginning ? Thx!

I can't test it out but try to use a variable for the date:

Code:

CurrDate=$(date)

find * -newer /home/copy.log -print | cpio -pvdmu /oldversions/"$CurrDate"

As I mentioned earlier you have to create a file the first time with the touch command with the last copy date and .... yes, the modifation time of the reference file is updated after the copy action with:

Code:

echo "Last copy on: `date`" >> copy.log

so find should looks for files older the reference file.

Regards

Hi!
Thanks for your last reply. I'm sorry to just come back to it now but I was busy with something else lately.

When I execute the script now

Code:

#!/bin/sh

cd /home

CurrDate=$(date)

find * -newer /home/copy.log -print | cpio -pvdmu /oldversions/"$CurrDate"

echo "Last copy on: `date`" >> copy.log

only one file is copied to the newly made folder. This is the -only- file is the home folder, the rest are (user)folders.
There should be something like userX, userY and userZ
(knowing that userX, userY and userZ have each a home dir with a few files)

Also, possibly, userX should not have access to the files of userY etc
But I guess thats just a matter of copying the file and folder permissions.

Oh, something else, for the date; is it possible to write the date like dd-mm-yyyy hh-mm ? now I get a very long and unhandy Date as foldername.

Thanks in advance !