diff --git a/src/libsystemd-network/sd-pppoe.c b/src/libsystemd-network/sd-pppoe.c
index 6f33541504..21ddaebdd2 100644
--- a/src/libsystemd-network/sd-pppoe.c
+++ b/src/libsystemd-network/sd-pppoe.c
@@ -22,6 +22,7 @@
 /* See RFC 2516 */
 
 #include <sys/ioctl.h>
+#include <linux/ppp_defs.h>
 #include <linux/ppp-ioctl.h>
 #include <net/if.h>
 #include <netinet/in.h>