diff --git a/vm/harness/scenarios/V-G1.yaml b/vm/harness/scenarios/V-G1.yaml
index 81fcfa0..95ea802 100644
--- a/vm/harness/scenarios/V-G1.yaml
+++ b/vm/harness/scenarios/V-G1.yaml
@@ -12,7 +12,7 @@ description: tc qdisc add dev ens4 root netem delay 400ms on the legacy instance
 inject:
   method: ssh
   host: legacy:busy
-  command: sudo tc qdisc add dev ens4 root netem delay 400ms
+  command: sudo tc qdisc replace dev ens4 root netem delay 400ms
 revert:
   method: ssh
   host: legacy:busy
diff --git a/vm/harness/scenarios/X-M2.yaml b/vm/harness/scenarios/X-M2.yaml
index 4ac9134..fa57be6 100644
--- a/vm/harness/scenarios/X-M2.yaml
+++ b/vm/harness/scenarios/X-M2.yaml
@@ -9,7 +9,7 @@ description: tc netem loss 50% for 90s on legacy instance 0
 inject:
   method: ssh
   host: legacy:0
-  command: sudo tc qdisc add dev ens4 root netem loss 50%
+  command: sudo tc qdisc replace dev ens4 root netem loss 50%
   wait_s: 90
 revert:
   method: ssh