Linux – How to safely clone a Linux VM in Hyper-V

hyper-vhyper-v-server-2012-r2linuxvirtualization

This is a home lab, so nothing critical. I have a base Linux ISO I'm installing for all my VMs, but the install takes a long time, and even once it's done, I still have to go install a ton of updates and a few packages. I would like to start cloning my VM's off of a base VM which I keep up-to-date.

My first thought was just to copy the VHDX file and spin up a new machine connected to that, but then I had second thoughts, since I realized I might run into conflicts with MAC addresses, IP addresses, machine names, etc (probably more I'm just not thinking of).

What do I need to do to minimize conflicts like this? Is there anything beyond MAC address, IP address, and host name which I ought to be worried about? Or can I really just copy the VHDX and spin up a new machine? Is there a better way to do this, while minimizing conflicts between the cloned machines?

EDIT: Any reason for the downvotes? I'm happy to revise or relocate my question if it's poorly constructed or belongs somewhere else.

Best Answer

For Windows guests you'd use Sysprep to generalize the VM that you're using as your template. I don't know if something similar exists for Linux.

As for the MAC address, each cloned VM will have it's own unique MAC address, which is generated by Hyper-V so that shouldn't be an issue.

As for the ip address, if you use DHCP to assign ip addresses then this shouldn't be an issue either.

The only real issue I see is with the hostname.

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EDIT: as per comment question - to delete the above rule:

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This will output something like:

Chain PREROUTING (policy ACCEPT)
num  target     prot opt source               destination         
1    REDIRECT   tcp  --  0.0.0.0/0            0.0.0.0/0           tcp dpt:8080 redir ports 8088
2    REDIRECT   tcp  --  0.0.0.0/0            0.0.0.0/0           tcp dpt:80 redir ports 8080

The rule you are interested in is nr. 2, so to delete it:

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Best Answer

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