diff --git a/tools/build/onos-buck b/tools/build/onos-buck
index 123a9b6..721bf46 100755
--- a/tools/build/onos-buck
+++ b/tools/build/onos-buck
@@ -45,7 +45,7 @@
     # Build it first
     pluginJar=$(NO_BUCKD=1 $BUCK build //tools/build/buck-plugin:onosjar --show-output 2>/dev/null | grep onosjar.jar | cut -d\  -f2)
 
-    CHK_NEW=$(cksum $pluginJar | cut -d' ' -f1-2)
+    CHK_NEW=$(cksum $ONOS_ROOT/$pluginJar | cut -d' ' -f1-2)
     CHK_OLD=$(cksum $ONOS_PLUGIN 2>/dev/null | cut -d' ' -f1-2)
     if [ "$CHK_NEW" != "$CHK_OLD" ]; then
         # diff plugins... if different, copy and restart buckd