Moving a machine from one VM or physical box to another

This is the simple case where all we have is one disk that needs cloning.

Assumptions for the following example

  1. Tools including backtrack distro available and permissible by company policy ( some c**ts get all agitated when sysadmins use a ‘knife’ to cut the ‘bread’ so be warned)
  2. Networking in place for the transfer preferable pre-organized IPs, gatway ,  DNS for resolving the updates like ssh etc.. , also verify the level of traffic your network guys are willing to tolerate for a long time this should be your –rate-limit value (remember this value is in Mega bytes so 9-10x the Megabit bandwidth.
  3. Cloning one disk is enough for the volumes to move. Compex LVM / software raids and concats or stripes need further steps.
  4. For the sake of example i assume this is a P2V but it’s just as good an approach in a V2V.


Points to perform :

  1. Download / Burn Backtrack or Knoppix
  2. Create a VM with large enough a disk and closely supported disk subsystem and NICs eg. SCSI and e1000
  3. Boot the two machines e.g. physical (source) and VM (target) with BT
  4. Enable ssh on both machines for a third person point of view even for monitoring the transfer
  5. Connect to the receiving VM booting into the live CD.
  6. Setup a screen session to avoid your disconnection from the session affecting the transit. Using screen -S transfer.
  7. run nc -l -p 19000 | bzip2 -d | dd bs=16M of =/dev/sda  replacing the 19000 with the port you want to use and /dev/sda with the disk you want to clone.
  8. Connect to the transmitting side.
  9. Setup a screen session to avoid your disconnection from the session affecting the transit. Using screen -S transfer.
  10. run dd bs=16M if=/dev/sda | pv –rate-limit 1M | bzip2 -c | nc 19000
    replacing the ip with the ip of the listener  connected in point 5, and you can skip the rate limit thingy (–rate-limit 1M) if you want full throttle..
  11. Once finished you can boot the target VM and reconfigure it as you please.


An extra help might be connecting to the target box in a target session and run iftop to see the transfers.




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