Update docker-apt-http-lxcs.sh

docker-apt-http-lxcs.sh

@@ -1,3 +1,4 @@
+```bash
 #!/usr/bin/env bash
 
 set -u
@@ -51,9 +52,13 @@ for CTID in $(pct list | awk 'NR>1 {print $1}'); do
 
         echo "  $FILE"
 
-        BACKUP="${FILE}.bak-$(date +%Y%m%d-%H%M%S)"
+        TIMESTAMP=$(date +%Y%m%d-%H%M%S)
+        BASENAME=$(basename "$FILE")
+        BACKUP_DIR="/root/apt-backups/docker"
+        BACKUP="${BACKUP_DIR}/${BASENAME}.${TIMESTAMP}.bak"
 
         pct exec "$CTID" -- sh -c "
+            mkdir -p '$BACKUP_DIR' &&
             cp '$FILE' '$BACKUP' &&
             sed -i \
                 's|https://download\.docker\.com|http://download.docker.com|g' \
@@ -86,3 +91,4 @@ done
 echo "=============================================="
 echo " Finished"
 echo "=============================================="
+```