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How to save an existing disk image from one node of a Testbed

If you have not done so yet:

• ​Register for an account
• ​Make a reservation on the Scheduler for a given testbed

Lets assume that you registered as user 'bob' and made a reservation for the 'sb1' testbed. You then access the 'sb1' console using the command:

 ssh bob@console.sb1.orbit-lab.org

Getting Started

Then, to save the existing disk image on node (1,1) of the 'sb1' testbed, use the command:

 omf save [1,1] 
 # will save the current disk image on node [1,1] of the 'sb1' testbed

The output of this image saving process will look like the following:

Domain information from the console: 'sb1'
Saving image from node '[1,1]' from domain 'sb1'... INFO init: NodeHandler Version 4.2.0 (1272)
 INFO init: Experiment ID: sb1_2008_07_20_23_38_04
 ...
 INFO stdlib: Waiting for nodes (Up/Down/Total): 0/1/1 - (still down: n_1_1)
 ...
 INFO n_1_1: - Saving disk image from node n_1_1 in the file 'node-1-1-2008-07-20-23-39-39.ndz'
 INFO n_1_1:   (disk images are located at: 'frisbee:/export/orbit/image/tmp')
 INFO prop.started: started = "true":String
 INFO exp: - SAVE_IMAGE process started at: Sun Jul 20 23:39:49 -0400 2008
 INFO exp:   (this may take a while, e.g. 5min+, depending of the size of your image)
 INFO exp: - Saving process finished correctly at: Sun Jul 20 23:47:20 -0400 2008
 INFO Experiment: DONE!
 INFO ExecApp: Application 'commServer' finished
 INFO run: Experiment sb1_2008_07_20_23_38_04 finished after 9:19
 done.

At the end of the saving process, you will have disk image file with the name: "node-1-1-2008-07-20-23-39-39.ndz" in the directory "/export/orbit/image/tmp" on the machine with the host name "frisbee". These information are all provided in the output displayed above.

You can then:

• install this disk image on a set of nodes, using the instructions described in this tutorial. In this example, to install the newly created disk image on node (1,2):

    omf load [1,2] tmp/node-1-1-2008-07-20-23-39-39.ndz
    # will install the disk image on node [1,2] of the 'sb1' testbed
  
  

• only for the purpose of making a backup of your image: log into the "repository" machine, and copy your image to your backup storage.

Learning More

The above disk image saving process is implemented as a special orbit experiment. As such, its execution will results in a log file as with any other orbit experiment. This log file should look like this​.

Each image created by the above saving process is a full hard-disk image, which can have arbitrary large file size (>200Mo or even more). As storage on the "frisbee" machine is limited, please be considerate in the number of images you save/use, and move any unused images to your own archival storage.

The generic omf command used above is the access point to control various ORBIT functions, such as the saving of a disk image from a node, with the sub-command "save". To see a list of all the available omf commands, you should type "omf help".

Finally, the complete available option/commands for the save function are given by "omf help save":

  omf help save


Save a disk image from a given node into an archive file

Usage:
      omf save [-h]
      omf save [NODE] [DOMAIN]
 
      With: 
      -h, --help    print this help message
      NODE          a valid node description 
                    (no default here, you have to enter a node!)
 
      Some Examples: 
                    omf save [5,10]
                    omf save [11,2] grid