Backing Up And Restoring Files

• Backing Up and Restoring Files.

        rsync -av /home/basil /backup/homes/

Note that there is no traling slash after basil, trailing / will copy all the files under the directory basil instead of the directory basil.

The (-a) option above preservs all the permissions,ownership, creation time.

        rsync -avz -e ssh /home/basil  192.168.0.11:/backup/homes/
       -z, --compress
              With  this option, rsync compresses any data from the files that
              it sends to the destination machine.  This option is  useful  on
              slow  connections.   The  compression  method  used  is the same
              method that gzip uses.

        -e, --rsh=COMMAND
              This  option  allows  you  to choose an alternative remote shell
              program to use for communication between the  local  and  remote
              copies  of  rsync.

• How to do auto backup using cron.

Add a file called backup to /etc/cron.daily/, set the permission to 755, and add the command line to the file. This will enable us to do daily backup of the directories above.

If you would like to enable the auto backup to a remote server, then, we need to setup ssh, scp, sftp without password to login.

• Password-less authentication.

Localmachine: basil

Remotemachine: trinity

        [basil@localhost ~]$ ssh-keygen -t dsa
        Generating public/private dsa key pair.

Enter file in which to save the key (/home/basil/.ssh/id_dsa):

        /home/basil/.ssh/id_dsa already exists.
        Overwrite (y/n)? y
        Enter passphrase (empty for no passphrase):
        Enter same passphrase again:
        Your identification has been saved in /home/basil/.ssh/id_dsa.
        Your public key has been saved in /home/basil/.ssh/id_dsa.pub.
        The key fingerprint is:
        d2:e6:c7:6c:18:ad:06:b2:0e:eb:08:57:7a:0b:77:3c basil@localhost
        [basil@localhost ~]$

Just press Enter on each request. And then copy the key to the remote machine trinity, On the remote machine `mkdir .ssh; chmod 0700 .ssh`

        [basil@localhost .ssh]$ scp id_ds
        id_dsa      id_dsa.pub
 scp id_dsa.pub trinity@192.168.0.11:/home/trinity/.ssh/authorized_keys2
        [trinity@localhost ~]$ ls -ld .ssh
        drwx------  2 trinity trinity 4096 Jun 15 17:15 .ssh/

Check..

         http://mikerubel.org/computers/rsync_snapshots

• Ftape-tool package

         http://metalab.unc.edu/pub/Linux/Kernel/tapes/

*Writing to CD's

Create an ISO9600 file system of the directory /home/basil

        $ mkisofs -R -o /var/basil.iso /home/basil

        [basil@localhost ~]$ cdrecord -scanbus
        scsibus1:
        1,0,0   100) 'ATAPI-CD' 'ROM-DRIVE-52MAX ' '52DI' Removable CD-ROM
        1,1,0   101) 'ATAPI   ' 'CD-RW 52X24     ' 'F.CZ' Removable CD-ROM
        1,2,0   102) *
        1,3,0   103) *
        1,4,0   104) *
        1,5,0   105) *
        1,6,0   106) *
        1,7,0   107) *


        $ cdrecord -v speed=2  dev=/media/cdrecorder -data /var/basil.iso [for ATAPI]

        $ cdrecord -v speed=2  dev=1,1,0  -data /var/basil.iso [for IDE]