Please note: ``l3_router`` option is also compatible with external routers. In this case NFVBench will use ``EXT`` chain.
+
+.. note:: Using a long NFVbench run test, end-to-end connectivity can be lost depending on ARP stale time SUT configuration.
+To avoid this issue, activate Gratuitous ARP stream using ``--gratuitous-arp`` or ``-garp`` option.
\ No newline at end of file