8. Data Backup

It is the user’s responsibility to backup all experimental data; we are keeping the data on our storage for six months and after that all data are permanently deleted. There are several ways to backup your data:

1. Use of the external hard disk, which can be mounted on a dedicated backup computer. Please do not attach your external disks to any other beamline computers. The current Linux operation system is most friendly to USB-2 hard disk drives with Linux (ext3) partition only. Any FAT32 partition slows down the whole network over the beamline and leads to computer freeze. We have several high capacity hard disks which can be borrowed for a short period of time if your external hard disk is not easily mounted or has any non-Linux partitions. Currently Linux does not support NTFS (Windows XP/Vista) or MAC partitions.

To mount your external hard drive: Plug-in the power to your USB/Firewire hard drive.

Plug-in the USB/Firewire cable from the dedicated backup computer to the hard drive. These cables are already connected to the backup computers USB hard drives normally get automounted to /media/usbdisk”I” where “I” is a number. Firewire drives also get automounted in a similar way to /media/ieee1394disk”I”. If the firewire drive does not automount, power cycle it while it is connected to the computer.

You may also use “sudo” to manually mount your disk (found by “fdisk –l”), if it is not recognized by the system; use “sudo –l” to see all available to you commands (use necat password).

To copy data from beamline data storage to your disk you can use “cp –R source_directory destination_directory”. Same thing can be done via rsync. The syntax is

rsync –avu /gpfs3/users/name/source_directory /mnt/usbdisk1/destination_directory. Rsync has certain advantages like it can do fast incremental file transfers.

It may be advantageous to used an automated specialized NESYNC script (find a desktop icon)

To unmount the external drive, right click on its icon on the desktop and select “Safely remove”, after that switch off the power and disconnect the USB/firewire cable.

2. FTP of your data to your home institution – use “sftp your_name@IP.address.your.computer” and use “mput *.img” command to transfer several files.

Another very powerful solution is to use RSYNC. rsync is a program that behaves in much the same way that rcp does, but has many more options and uses the rsync remote-update protocol to greatly speed up file transfers when the destination file already exists. The rsync remote-update protocol allows rsync to transfer just the differences between two sets of files across the network connection, using an efficient checksum-search algorithm. Check man-pages for specific options.

3. DVD creation. VERY slow and it is NOT recommended or supported.

On the dedicated backup computer you insert blank DVD disk (DVD+R is the fastest format) in the top tray, wait until “k3b” window appears, and you should drag and drop (or select) all the files you need to write into this window, check that the size of all files less than 4.3Gb, go to File pulldown menu and select “Write to disk..”, (you may want to change the label of the disk), press OK.

Blank DVDs are available from the APS stockroom or from you local support personnel.

“sdvdbackup /full_dir_name” will backup all your files to several DVDs.

4. Copying crystal images from the MD2 computer. On MD2 computer, copy your images (which are by default saved under c:/dev/APS_NECAT/MD2/images, which has a short cut on the desktop under icon “images”) to NEShare shortcut folder on the desktop. This is a samba shared directory on the on the backup computer (IP name Gold :164.54.212.124). Now on Gold, you may copy these images from /mnt/NEShare/necat/ to your backup disk.