diff --git a/package/on-boot.sh b/package/on-boot.sh
index 91cb603..e0bd0f0 100755
--- a/package/on-boot.sh
+++ b/package/on-boot.sh
@@ -1,7 +1,30 @@
 #!/bin/sh
 set -e
 
-OS_VERSION="${FW_VERSION:-$(ubnt-device-info firmware_detail | grep -oE '^[0-9]+')}"
+if [ -x "$(which ubnt-device-info)" ]; then
+  OS_VERSION="${FW_VERSION:-$(ubnt-device-info firmware_detail | grep -oE '^[0-9]+')}"
+elif [ -f "/usr/lib/version" ]; then
+  # UCKP == Unifi CloudKey Gen2 Plus
+  # example /usr/lib/version file contents:
+  # UCKP.apq8053.v2.5.11.b2ebfc7.220801.1419
+  # UCKP.apq8053.v3.0.17.8102bbc.230210.1526
+  # UCKG2 == UniFi CloudKey Gen2
+  # example /usr/lib/version file contents:
+  # UCKG2.apq8053.v3.1.13.3584673.230626.2239
+  if [ "$(grep -c '^UCKP.*\.v[0-9]\.' /usr/lib/version)" = '1' ]; then
+    OS_VERSION="$(sed -e 's/UCKP.*.v\(.\)\..*/\1/' /usr/lib/version)"
+  elif [ "$(grep -c '^UCKG2.*\.v[0-9]\.' /usr/lib/version)" = '1' ]; then
+    OS_VERSION="$(sed -e 's/UCKG2.*.v\(.\)\..*/\1/' /usr/lib/version)"
+  else
+    echo "Could not detect OS Version.  /usr/lib/version contains:"
+    cat /usr/lib/version
+    exit 1
+  fi
+else
+  echo "Could not detect OS Version.  No ubnt-device-info, no version file."
+  exit 1
+fi
+
 
 if [ "$OS_VERSION" = '1' ]; then
   TAILSCALE_ROOT="/mnt/data/tailscale"