Proxmox_KVM_Restore_files, version 1

Proxmox_KVM_Restore_files.md

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+Proxmox KVM : How to restore files from dump/backup
+===================================================
+
+Just a simple procedure that was a bit tricky to find on the web. I
+needed to restore a few files that got overwritten on a server which is
+a KVM virtual machine running on a Proxmox host. They are several ways
+to achieve this but I found this to be the simplest and cleanest way :
+
+-   Do a manual restore by using a non existing VMID (YYY):
+        qmrestore dump/vzdump-qemu-XXX-DATE-TIME.vma YYY
+
+-   Mount the partition :
+        modprobe nbd max_part=16
+        qemu-nbd --connect=/dev/nbd0 images/YYY/vm-YYY-disk-1.qcow2 
+        vgscan 
+          Reading all physical volumes.  This may take a while...
+          Found volume group "vgmain" using metadata type lvm2
+          Found volume group "pve" using metadata type lvm2
+        vgchange -ay vgmain
+          2 logical volume(s) in volume group "vgmain" now active
+        mount /dev/vgmain/root /mnt/XXX
+
+-   Do not forget to unmount the drive afterwards :
+        umount /mnt/XXX
+        vgchange -an vgmain
+        qemu-nbd -d /dev/nbd0 
+        /dev/nbd0 disconnected
+        rmmod nbd
+
+-   You can then remove wour fake VM if you do not need to recover any
+    more files :
+        rm -r /var/lib/vz/images/YYY/
+
+Troubleshooting
+---------------
+
+If `vgscan` doesn’t return anything and a manual partprobe returns the
+following :
+
+    partprobe /dev/nbd0
+    Error: Error informing the kernel about modifications to partition /dev/nbd0p1 -- Invalid argument.  This means Linux won't know about any changes you made to /dev/nbd0p1 until you reboot -- so you shouldn't mount it or use it in any way before rebooting.
+    Error: Failed to add partition 1 (Invalid argument)
+
+  
+then you have forgotten to add the `max_part` parameters to your
+`modprobe` command
+