diff --git a/tests/topotests/isis_snmp/test_isis_snmp.py b/tests/topotests/isis_snmp/test_isis_snmp.py
index ddef08008b..0ec1fa0e53 100755
--- a/tests/topotests/isis_snmp/test_isis_snmp.py
+++ b/tests/topotests/isis_snmp/test_isis_snmp.py
@@ -104,6 +104,7 @@ def build_topo(tgen):
     switch = tgen.add_switch("s6")
     switch.add_link(tgen.gears["r2"])
     switch.add_link(tgen.gears["r3"])
+    switch.add_linker(tgen.gears["r3"])
 
 
 def setup_module(mod):