ONOS-737: regexp for grabbing OC* variables changed

Change-Id: Id5651ffb41230a39c6ed68e1605feaf3c0aa337b
diff --git a/tools/test/bin/onos-service b/tools/test/bin/onos-service
index eab52ed..d65b521 100755
--- a/tools/test/bin/onos-service
+++ b/tools/test/bin/onos-service
@@ -36,7 +36,7 @@
     start|stop|restart|status)
         # Select the target
         if [ "${1}" = "--cell" ]; then
-            nodes=$(env | sort | egrep "OC[0-9]+" | cut -d= -f2)
+            nodes=$(env | sort | egrep "^OC[0-9]+" | cut -d= -f2)
         else
             nodes=$(find_node ${1:-$OCI})
         fi