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I've just cloned a computer (see here for my process, if it's relevant) and I want to make sure it will be OK on the same network as the original.

I've changed the host name back to what it was pre cloning, so there won't be duplicates on the network, but I want to make sure I make any other necessary fixes before I put the computers running Ubuntu 12.04, on the same network. Is there anything else I need to do before I link them back up?

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StephenTG
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  • Are you using DHCP to get your IP address or is it hardwired? Hardwired will require a change. – ubfan1 Aug 19 '13 at 17:00
  • @ubfan1 Cloning didn't seem to change the ip from what it was before I cloned it. Does that mean I'm using DHCP? – StephenTG Aug 19 '13 at 17:01
  • No, DHCP should give you a different address for the two machines. The first machine hooked up will probably get the old IP, the second one should get a new one. – ubfan1 Aug 19 '13 at 17:07
  • @ubfan1 Neither machine has changed ip addresses from what they had before the clone. – StephenTG Aug 19 '13 at 17:10
  • Then they're hardwired (if both machines are hooked up at the same time and have the same IP). Look in file /etc/network/interfaces to see the IP setup. – ubfan1 Aug 19 '13 at 17:11
  • @ubfan1 Line 1: auto lo Line 2: iface lo inet loopback – StephenTG Aug 19 '13 at 17:13
  • The two computers have different addresses (Comp 1 had .193, comp 2 had .189, now comp 1 still has .193 and comp 2 still has .189) Sorry if my wording has been ambiguous. – StephenTG Aug 19 '13 at 17:15
  • Then they are different, not hardwired, so you should be OK. – ubfan1 Aug 19 '13 at 17:27
  • See also [my cloning guide](http://askubuntu.com/questions/25633/how-to-migrate-user-settings-and-data-to-new-machine/5025#5025). – Gilles 'SO- stop being evil' Sep 19 '13 at 18:15

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You must change the host name; you've already done that.

Depending on how your computer obtains its IP address, you may need to update it.

  • If your computer uses DHCP and is assigned an essentially random address from the dynamic IP address pool, each computer will naturally gets its own address.
  • If your computer gets its IP address via DHCP based on the host name, you should update the database in the DHCP server.
  • If your computer has a static IP address, you'll need to change it. Check your network configuration to see which IP addresses are permissible and not taken yet. Static IP address are usually configured in /etc/network/interfaces, but if you used wicd or NetworkManager then you'll need to update the relevant configuration.

You must change the SSH host key. Each computer needs to have its own private key. Remove /etc/ssh/ssh_host_*_key* and run dpkg-reconfigure openssh-server to generate new host keys.

Gilles 'SO- stop being evil'
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