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Saving root filesystem with tar

Hello guys! I am planning to tar my root partition to temporarily move it to another HDD and later back on the old one and untar, so while it's on a new drive I can do some things with the old one. And I wanted to make sure I won't screw it up. Is this set of option (from LiveCD, in a mounted root directory) enough for tar to save and restore all OS files correctly:

Code:

tar cpf sda1.tar *

Or do I need to add some option to handle links or anything else?

I think you will need to exclude all temporary file systems (/tmp, /sys, /proc ...)

If you do exclude the above I would suggest placing the tar file on one of them as including within the area being tarred can throw errors (just warnings I think).

As doing the main system you would need to be root, hence -p is already the default

you may also wish to consider compressing it depending on the size of the data and the room on the drive

Quote:

Originally Posted by grail (Post 5091723)

I think you will need to exclude all temporary file systems (/tmp, /sys, /proc ...)

Will I? As I mentioned, "from LiveCD, in a mounted root directory". So yes, tar file will have to be put somewhere else, but there will be no /proc or /sys dirs/filesystems on sda1 mounted to, say, /mnt when doing it all from some LiveCD. Right?

Quote:

Originally Posted by Mr. Alex (Post 5091730)

Indeed, but you still may to exclude /tmp, unless it is empty anyway.

I use a shell script for backups - even when on line.

Code:

#!/bin/sh

# backup.sh - a simple backup script creating tar files

# usage:

#        backup.sh [ref]

# where:

#        ref        - reference name of filesystem to backup.

# note:

#        If no ref is specified then all file systems will be backed up.

#        Reference names are one (or more) of root, boot, or home;

#        separated by spaces.

#------------------------------------------------------------------------

# configuration

#        Adding filesystems to the Base list requires modifying

#        the evaluation and the list of real filesystems.

#        This script may be redone as a perl script to simplify this...

#------------------------------------------------------------------------



Base="root boot home"

Release="Fedora16"

TARGET="/home/sys"

HOST="panther"



#------------------------------------------------------------------------

# evaluate options



if [ "$*" == "" ]; then

  list="${Base}"

else

  list="$*"

fi



for item in $list; do

    case $item in

        root);;

        boot);;

        home);;

        *)

          echo "Only one of \"${Base}\" can be used"

          exit 1 

        ;;

    esac

done



#------------------------------------------------------------------------

# perform the backup



DATE=`date +"%Y.%m.%d"`



# protect the generated tar files



umask 077



# verify destination exists



if [ ! -d "${TARGET}/${HOST}" ]; then

    mkdir ${TARGET}/${HOST}

fi



if [ ! -d "${TARGET}/${HOST}/${Release}" ]; then

    mkdir ${TARGET}/${HOST}/${Release}

fi



# backup the list of filesystems



for item in ${list}; do



    echo "${item} -"`date +%H:%M:%S`

    case ${item} in

        root)        frm="/"

                xclude=" --exclude /tmp/* --exclude /var/tmp/* --exclude=/home"

                ;;

        boot)        frm="/boot"

                xclude=""

                ;;

        home)        frm="/home"

                xclude="";;

    esac 

    tar --one-file-system --selinux --acls --xattrs -z \

        ${xclude} \

        -cf \

                ${TARGET}/${HOST}/${Release}/${item}.${DATE}.tgz ${frm}



done

echo "done  -"`date +%H:%M:%S`



exit

Tar will identify files that change while it is performing a backup... and normally this is not a problem as the files are the log files...

Using the "--one-file-system" eliminates the need to specifically exclude /proc, /sys, and any mounted filesystem as tar will only create an entry for the mountpoint, but not backup any of the files within.