Differences between revisions 23 and 29 (spanning 6 versions)

Domain Cloning

Once a template system has been installed, that system can be cloned. virt-clone will automatically change the MAC address of your network device.

Cloning

Use the script below to clone your template.

domain_clone.sh

   1 #!/bin/sh
   2 
   3 LVM_GROUP="vg2"
   4 NAME_ORIGINAL="stretch-template"
   5 LVM_NAME_ORIGINAL="kvm_${NAME_ORIGINAL}_vda"
   6 LVM_SIZE_ORIGINAL=`lvs /dev/${LVM_GROUP}/${LVM_NAME_ORIGINAL} -o LV_SIZE --noheadings --units B --nosuffix`
   7 NAME_CLONE="stretch-clone"
   8 LVM_NAME_CLONE="kvm_${NAME_CLONE}_vda"
   9 
  10 if [ $# -gt 0 ]
  11 then
  12         NAME_CLONE=${1}
  13         LVM_NAME_CLONE="kvm_${NAME_CLONE}_vda"
  14 fi
  15 
  16 if [ ! -e /dev/${LVM_GROUP}/${LVM_NAME_CLONE} ]
  17 then
  18         # create lvm partition
  19         lvcreate --size ${LVM_SIZE_ORIGINAL}B --name ${LVM_NAME_CLONE} ${LVM_GROUP}
  20 
  21         # clone the domain
  22         virt-clone --original ${NAME_ORIGINAL} --name ${NAME_CLONE} --file /dev/${LVM_GROUP}/${LVM_NAME_CLONE} --check path_in_use=off,path_exists=off
  23 else
  24         echo "${0}: refusing to overwrite existing domain"
  25 fi

Make a clone.

./domain_clone.sh clone

Console Access

Remove console access by editing the domain.

Memory

Increase or decrease amount of memory by editing the domain.

Unique keys for ssh

Make sure your clone does indeed have unique ssh keys. This is a really important step when cloning. Consider all your clones had the same ssh keys, that would really be a mess.

rm /etc/ssh/ssh_host_*
dpkg-reconfigure openssh-server
service sshd restart

Hostname

Change the hostname of your new guest.

cp /etc/hosts /etc/hosts.bak
sed -i "s/stretch-template/clone/g" /etc/hosts
cp /etc/hostname /etc/hostname.bak
sed -i "s/stretch-template/clone/g" /etc/hostname

Root password

Make sure to change the root password.

passwd

-  ⇤ ← Revision 23 as of 2017-11-11 22:45:20 → 
  Size: 1794
  Editor: shran
  Comment:
+   ← Revision 29 as of 2017-12-08 14:08:24 → ⇥
  Size: 1946
  Editor: Kristian Kallenberg
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 2:
-Line 6:
+Line 5:
-Line 43:
+Line 41:
-== Cleanup ==
+== Console Access ==
Remove console access by [[Domain Editing|editing the domain]].
-Line 45:
+Line 44:
-=== Hostname ===
+== Memory ==
Increase or decrease amount of memory by [[Domain Editing|editing the domain]].
 Line 47:
-Your new system will need a new hostname

 * /etc/hostname
 * /etc/hosts

{{{
sed -i 's/stretch-template/clone/g' /etc/hosts
sed -i 's/stretch-template/clone/g' /etc/hostname
}}}

=== sshd ===

Make sure the ssh keys are unique.
+== Unique keys for ssh ==
Make sure your clone does indeed have unique ssh keys. This is a really important step when cloning. Consider all your clones had the same ssh keys, that would really be a mess.
-Line 64:
+Line 53:
+service sshd restart
-Line 66:
+Line 56:
-=== Root Password ===
+== Hostname ==
Change the hostname of your new guest.
{{{
cp /etc/hosts /etc/hosts.bak
sed -i "s/stretch-template/clone/g" /etc/hosts
cp /etc/hostname /etc/hostname.bak
sed -i "s/stretch-template/clone/g" /etc/hostname
}}}
-Line 68:
+Line 65:
-Reset your root passwd.
+== Root password ==
Make sure to change the root password.
-Line 73:
+Line 70:
-== Update ==

Since the template can be quite old, you might as well update it.

{{{
apt-get update
apt-get upgrade
}}}

== Console Access ==

Remove console access by [[Domain Editing|editing the domain]].