#!/bin/bash
#https://pastebin.com/URrtG3hP
set -e
 
if [ ! -z "$1" ]; then
 
if [ ! -d "/var/log/kvm_backup" ]; then
    mkdir -vp "/var/log/kvm_backup" | tee -a '/var/log/kvm_backup/'$1'.log'
fi
 
echo "" | tee -a '/var/log/kvm_backup/'$1'.log'
echo "" | tee -a '/var/log/kvm_backup/'$1'.log'
 
##########################################
#backupdir=''$PWD'/kvm_backup'
backupdir='/backup/backup/kvm_backup'
keepbackups=4
##########################################
 
if ! command -v virsh &> /dev/null; then
    echo "Error: virsh command not found. Please install libvirt-bin package." | tee -a '/var/log/kvm_backup/'$1'.log'
    exit 1
fi
 
if ! command -v rsync &> /dev/null; then
    echo "Error: rsync command not found. Please install rsync package." | tee -a '/var/log/kvm_backup/'$1'.log'
    exit 1
fi
 
if [ ! -d "$backupdir" ]; then
    echo "Error: Backup directory does not exist." | tee -a '/var/log/kvm_backup/'$1'.log'
    exit 1
fi
  
    datum=`date +"%s-%d-%m-%y"`
    name="$1"
    moment=''$name'_'$datum''
    running=`virsh list|grep $1|tr -s ' '|cut -d ' ' -f 3`
    disks=`virsh domblklist "$1" --details|grep qcow2|tr -s ' '|awk '{print $3 "|" $4}'`
    snapdir=''$backupdir'/'$1'_'$datum''
 
    if [ "$running" == "$1" ]; then
 
        if [ ! -d "$backupdir" ]; then
            mkdir -p "$backupdir"
        fi
 
        if [ -d "$backupdir" ]; then
            if [ ! -z "$disks" ]; then
            
                mkdir -p $snapdir
                
                if [ -d "$snapdir" ]; then
 
                    for disk in $disks; do
 
                        typ=`echo $disk | cut -d '|' -f 1`
                        file=`echo $disk | cut -d '|' -f 2`
                        base=`basename $file`
                        filename=''$backupdir'/'$1'_'$datum'/'$base''
 
                        echo 'INFO: Starting Backup of '$1'_'$datum'' | tee -a '/var/log/kvm_backup/'$1'.log'   
 
                        if [ ! -f "$file" ]; then
 
                            echo "####################################################################################" | tee -a '/var/log/kvm_backup/'$1'.log'
                            echo "# WARNING:                                                                         #" | tee -a '/var/log/kvm_backup/'$1'.log'
                            echo "# Source File is deleted. Try Backup from /proc                                    #" | tee -a '/var/log/kvm_backup/'$1'.log'
                            echo "# Need to hard crash (kill -9) the VM and recover the Source File from Backup File #" | tee -a '/var/log/kvm_backup/'$1'.log'
                            echo "####################################################################################" | tee -a '/var/log/kvm_backup/'$1'.log'
                             
                            delid=`lsof -wXT | grep "$base" | grep deleted | head -n 1|tr -s ' '| awk '{print $2}'`
                            olddisk=`ls -l /proc/"$delid"/fd/ | grep "$base"|tr -s ' '| awk '{print $9}'`
 
                            kill -STOP "$delid"
 
                            echo "WARN: Backup $1 -> /proc/$delid/fd/$olddisk -> $filename" | tee -a '/var/log/kvm_backup/'$1'.log'
           
                            if ! dd if="/proc/$delid/fd/$olddisk" of="$filename" bs=1M status=progress; then
                                echo "ERROR: Failed to create Backup of $1." | tee -a '/var/log/kvm_backup/'$1'.log'
                                exit 1  
                            fi 
 
                            kill -CONT "$delid"
 
                            echo "INFO: Backup "$1" -> /proc/"$delid"/fd/"$olddisk" to "$filename" complete." | tee -a '/var/log/kvm_backup/'$1'.log'
 
                        else
                           
                            if ! virsh snapshot-create-as --domain $1 --name $moment \
                                --diskspec $typ,file=''$filename'' \
                                --disk-only --atomic \
                                --no-metadata; then
                                echo "ERROR: Failed to create snapshot." | tee -a '/var/log/kvm_backup/'$1'.log'
                                exit 1  
                            fi
 
                            if ! rsync -avhW --progress --log-file='/var/log/kvm_backup/'$1'.log' ''$file'' ''$backupdir'/'$1'_'$datum'/'; then
                                echo "ERROR: Failed to copy disk image." | tee -a '/var/log/kvm_backup/'$1'.log'
                                exit 1
                            else
                            
                                
                                virsh blockcommit "$1" "$typ" --wait --active --verbose
                                virsh blockjob "$1" "$filename" --pivot
                                
                                echo "INFO: Backup "$1" -> "$file" to "$backupdir"/"$1"_"$datum" complete." | tee -a '/var/log/kvm_backup/'$1'.log'
                            fi
 
                        fi
 
                    done
 
                    virsh dumpxml "$1" > ''$backupdir'/'$1'_'$datum'/'$1'.xml'
 
 
            networks=$(virsh domiflist "$1" | grep network | tr -s ' ' | awk '{ print $3}')
 
            for network in $networks; do
            virsh net-dumpxml "$network" > ''$backupdir'/'$1'_'$datum'/'$network'.xml'
            done
 
 
            
            anz=`ls -d $backupdir/$1*|wc -l`
 
            if (( "$anz" > "$keepbackups" )); then
                cleanfile=`ls -d $backupdir/$1*|sort|head -n 1`
                
                if [ ! -z "$cleanfile" ]; then
                    rm -vdR "$cleanfile"
                fi
            fi
 
                fi
            fi
        fi
    else
        echo "ERROR: VM not running."
    fi
else
    echo "ERROR: Missing VM Name."
fi