diff --git a/target/linux/ar71xx/files/arch/mips/ath79/mach-ubnt-xm.c b/target/linux/ar71xx/files/arch/mips/ath79/mach-ubnt-xm.c
index bb5b28fc05..7f7d1f95df 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/mach-ubnt-xm.c
+++ b/target/linux/ar71xx/files/arch/mips/ath79/mach-ubnt-xm.c
@@ -279,6 +279,7 @@ static void __init ubnt_unifi_outdoor_plus_setup(void)
 	ath79_register_eth(0);
 	ath79_register_eth(1);
 
+	ap9x_pci_get_wmac_data(0)->ubnt_hsr = true;
 	ap91_pci_init(ee, NULL);
 
 	ath79_register_leds_gpio(-1, ARRAY_SIZE(ubnt_unifi_outdoor_plus_leds_gpio),