Editing Futotemporarywikipage (section)

=== Basic Restore ===

By “basic restore” I mean what to do when you messed up a program configuration or deleted files inside a virtual machine or corrupted something accidentally. You want to go back to the image of the virtual machine you had before, on the same happycloud host computer.

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==== 8.1 Before You Start ====

I’m assuming the following is true: - Your virtual machine is already defined in Virtual Machine Manager(you see it when you run virtual machine manager GUI) - Your backups are in <code>/mediapool/vmbackups</code> - The backups were created using the qemu-img backup script I provided above - You just need to restore the virtual machine’s disk because you messed up some files or programs

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==== 8.2 Find Your Backup ====

# List available backups for your virtual machine:

<pre>ls -l /mediapool/vmbackups/name-of-your-virtual-machine-*.qcow2</pre>
You’ll see files named like this: - <code>name-of-your-virtual-machine-20240101.qcow2</code> - <code>name-of-your-virtual-machine-20240108.qcow2</code>

These are the disk image files that have all of the data/programs/databases/operating system.

Each backup will have an XML file to go with it: - <code>name-of-your-virtual-machine-20240101.xml</code> - <code>name-of-your-virtual-machine-20240108.xml</code>

These are the files that tell virtual machine manager all of the details about your virtual machine(RAM/CPU, hardware setup, etc.)

Pick the most recent backup before you screwed something up.

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==== Fast Restore: ====

# Turn off the virtual machine

<pre># Shut down the virtual machine gracefully
virsh shutdown name-of-your-virtual-machine

# Wait until it's actually off. Check status with:
virsh list --all</pre>
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<li>Backup Current Disk (just in case)</li></ol>

<pre># Move the current (messed up/broken) disk with date
mv /var/lib/libvirt/images/name-of-your-virtual-machine.qcow2 /var/lib/libvirt/images/name-of-your-virtual-machine.qcow2.broken-$(date +%Y%m%d)</pre>
<ol start="3" style="list-style-type: decimal;">
<li>Restore Backup</li></ol>

<pre># a cool command to put the virtual machine back where it was
qemu-img convert -p -f qcow2 -O qcow2 /mediapool/vmbackups/name-of-your-virtual-machine-20240101.qcow2 /var/lib/libvirt/images/name-of-your-virtual-machine.qcow2

# set permissions so that our virtual machine management stuff can use it.
chown libvirt-qemu:kvm /var/lib/libvirt/images/name-of-your-virtual-machine.qcow2
chmod 644 /var/lib/libvirt/images/name-of-your-virtual-machine.qcow2</pre>
<ol start="4" style="list-style-type: decimal;">
<li>Start the Virtual Machine</li></ol>

<pre>virsh start name-of-your-virtual-machine</pre>
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==== Check the Restore ====

# Watch the virtual machine console in Virtual Machine Manager to make sure it boots
# Try logging in when it’s up
# Check that services(mailcow, immich, syncthing) actually work

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