diff --git a/usr.sbin/makefs/cd9660/iso9660_rrip.c b/usr.sbin/makefs/cd9660/iso9660_rrip.c
--- a/usr.sbin/makefs/cd9660/iso9660_rrip.c
+++ b/usr.sbin/makefs/cd9660/iso9660_rrip.c
@@ -629,28 +629,29 @@ cd9660_createSL(cd9660node *node)
 			}
 		}
 	}
 }
 
 int
 cd9660node_rrip_px(struct ISO_SUSP_ATTRIBUTES *v, fsnode *pxinfo)
 {
-	v->attr.rr_entry.PX.h.length[0] = 36;
+	v->attr.rr_entry.PX.h.length[0] = 44;
 	v->attr.rr_entry.PX.h.version[0] = 1;
 	cd9660_bothendian_dword(pxinfo->inode->st.st_mode,
 	    v->attr.rr_entry.PX.mode);
 	cd9660_bothendian_dword(pxinfo->inode->st.st_nlink,
 	    v->attr.rr_entry.PX.links);
 	cd9660_bothendian_dword(pxinfo->inode->st.st_uid,
 	    v->attr.rr_entry.PX.uid);
 	cd9660_bothendian_dword(pxinfo->inode->st.st_gid,
 	    v->attr.rr_entry.PX.gid);
+	cd9660_bothendian_dword(pxinfo->inode->st.st_ino,
+	    v->attr.rr_entry.PX.serial);
 
-	/* Ignoring the serial number for now */
 	return 1;
 }
 
 int
 cd9660node_rrip_pn(struct ISO_SUSP_ATTRIBUTES *pn_field, fsnode *fnode)
 {
 	pn_field->attr.rr_entry.PN.h.length[0] = 20;
 	pn_field->attr.rr_entry.PN.h.version[0] = 1;
diff --git a/usr.sbin/makefs/cd9660/iso9660_rrip.h b/usr.sbin/makefs/cd9660/iso9660_rrip.h
--- a/usr.sbin/makefs/cd9660/iso9660_rrip.h
+++ b/usr.sbin/makefs/cd9660/iso9660_rrip.h
@@ -98,17 +98,17 @@
 #define SL_FLAGS_ROOT	        8
 
 typedef struct {
 	ISO_SUSP_HEADER		 h;
 	u_char mode		[ISODCL(5,12)];
 	u_char links		[ISODCL(13,20)];
 	u_char uid		[ISODCL(21,28)];
 	u_char gid		[ISODCL(29,36)];
-	u_char serial		[ISODCL(37,44)];/* Not used */
+	u_char serial		[ISODCL(37,44)];
 } ISO_RRIP_PX;
 
 typedef struct {
 	ISO_SUSP_HEADER		 h;
 	u_char high		[ISODCL(5,12)];
 	u_char low		[ISODCL(13,20)];
 } ISO_RRIP_PN;