diff --git a/roles/lmn_vm/files/vm-netboot b/roles/lmn_vm/files/vm-netboot
index 2b18831..19036a9 100755
--- a/roles/lmn_vm/files/vm-netboot
+++ b/roles/lmn_vm/files/vm-netboot
@@ -1,24 +1,30 @@
 #!/usr/bin/bash
 #
-# Start a netboot VM
+# Start a netboot VM connected to macvtap device and fraction of mem/cpus
 #
 set -eu
 
-if [[ $# -eq 0 ]] ; then
-    arg="--memory 4096 --vcpu 4"
-fi
-
-# find macvtap interface MAC address:
-MAC="$(ip link | grep -A1 "vm-macvtap" | \
+mac="$(ip link | grep -A1 "vm-macvtap" | \
 	  sed -nE "s%\s+link/ether ([[:xdigit:]:]{17}) .+%\1%p")"
 
+if [[ $# -eq 0 ]] ; then
+    mem=$(sed -En "s/^MemTotal:\s+([0-9]+)\s+kB/\1/p" /proc/meminfo)
+    cpu=$(sed -En "0,/^cpu cores/s/^cpu cores\s+:\s+([0-9]+)/\1/p" /proc/cpuinfo)
+    arg="--memory $((mem/2048)) --vcpu $((cpu/2))"
+    echo "Set options: $arg"
+fi
+
+loader='/usr/share/OVMF/OVMF_CODE_4M.fd,\
+loader.readonly=yes,loader.type=pflash,\
+nvram.template=/usr/share/OVMF/OVMF_VARS_4M.fd'
+
+type="ethernet,mac=${mac},target.dev=vm-macvtap,xpath1.set=./target/@managed=no"
+
 XDG_CONFIG_HOME="/tmp/${UID}/.config" \
-	       exec virt-install \
+	       exec "virt-install \
                --name bookworm \
                --osinfo debiantesting \
                --nodisks --import \
-               --pxe --boot loader=/usr/share/OVMF/OVMF_CODE_4M.fd,\
-loader.readonly=yes,loader.type=pflash,\
-nvram.template=/usr/share/OVMF/OVMF_VARS_4M.fd \
-               --network type=ethernet,mac=${MAC},\
-target.dev=vm-macvtap,xpath1.set=./target/@managed=no $@ ${arg:-}
+               --pxe --boot loader=$loader \
+               --network type=$type \
+	       $* ${arg:-}"