Support older kernels

Support older kernels

run/network.sh

@@ -112,8 +112,10 @@ configureNAT () {
   iptables -t nat -A PREROUTING -i "${VM_NET_DEV}" -p tcp  -j DNAT --to $VM_NET_IP
   iptables -t nat -A PREROUTING -i "${VM_NET_DEV}" -p udp  -j DNAT --to $VM_NET_IP
 
+  if (( KERNEL > 4 )); then
     # Hack for guest VMs complaining about "bad udp checksums in 5 packets"
     iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM --checksum-fill || true
+  fi
 
   #Enable port forwarding flag
   [[ $(< /proc/sys/net/ipv4/ip_forward) -eq 0 ]] && sysctl -w net.ipv4.ip_forward=1

run/run.sh

@@ -3,8 +3,8 @@ set -eu
 
 # Docker environment variabeles
 
-: ${URL:=''}.                     # URL of the PAT file
-: ${DEBUG:=''}.               # Enable debug mode
+: ${URL:=''}                      # URL of the PAT file
+: ${DEBUG:=''}                # Enable debug mode
 : ${ALLOCATE:='Y'}       # Preallocate diskspace
 : ${CPU_CORES:='1'}     # Amount of CPU cores
 : ${DISK_SIZE:='16G'}    # Initial data disk size
@@ -13,6 +13,8 @@ set -eu
 echo "Starting Virtual DSM for Docker v${VERSION}..."
 
 STORAGE="/storage"
+KERNEL=$(uname -r | cut -b 1)
+
 [ ! -d "$STORAGE" ] && echo "Storage folder (${STORAGE}) not found!" && exit 69
 [ ! -f "/run/run.sh" ] && echo "Script must run inside Docker container!" && exit 60
 
@@ -67,4 +69,8 @@ set -m
 )
 set +m
 
+if (( KERNEL > 4 )); then
   pidwait -F "${_QEMU_PID}" & wait $!
+else
+  tail --pid "$(cat ${_QEMU_PID})" --follow /dev/null & wait $!
+fi