1 files changed, 27 insertions, 0 deletions
diff --git a/scripts/testing/net-scenarios/20-rival-manager.sh b/scripts/testing/net-scenarios/20-rival-manager.sh
new file mode 100644
index 0000000..0d7836b
--- /dev/null
+++ b/scripts/testing/net-scenarios/20-rival-manager.sh
@@ -0,0 +1,27 @@
+# shellcheck shell=bash disable=SC2034  # sourced by run-net-scenarios.sh
+# Scenario: a rival network manager active alongside NetworkManager is disabled.
+#
+# dhcpcd (or systemd-networkd / iwd) running next to NM fights it for the link.
+# Break by enabling dhcpcd; the fix disables it, and the chain resets to
+# reconnect. Requires dhcpcd installed in the target.
+SCENARIO_DESC="an active rival manager (dhcpcd) is disabled"
+SCENARIO_GROUP="control-plane"
+
+scenario_break() {
+    nexec "systemctl enable --now dhcpcd"
+}
+
+scenario_diagnose_expect() {
+    # The verdict fires only when the link is also failing; in a fresh target
+    # with no configured uplink that holds, so the rival should be named.
+    ndoctor_json ".report.control_plane.rivals | index(\"dhcpcd\")" \
+        | grep -vqx null
+}
+
+scenario_fix() {
+    nfix
+}
+
+scenario_assert() {
+    ! nexec "systemctl is-active dhcpcd >/dev/null 2>&1"
+}