2 files changed, 3 insertions, 1 deletions

diff --git a/plugins/check_smtp.c b/plugins/check_smtp.c
index 324549d4..fd492294 100644
--- a/plugins/check_smtp.c
+++ b/plugins/check_smtp.c
@@ -697,6 +697,8 @@ check_smtp_config_wrapper process_arguments(int argc, char **argv) {
                         } else {
                                 usage2(_("Invalid hostname/address"), argv[c]);
                         }
+                } else {
+                        result.config.server_address = strdup("localhost");
                 }
         }
 
diff --git a/plugins/check_smtp.d/config.h b/plugins/check_smtp.d/config.h
index c8660445..0a6511ef 100644
--- a/plugins/check_smtp.d/config.h
+++ b/plugins/check_smtp.d/config.h
@@ -52,7 +52,7 @@ typedef struct {
 check_smtp_config check_smtp_config_init() {
         check_smtp_config tmp = {
                 .server_port = SMTP_PORT,
-                .server_address = strdup("localhost"),
+                .server_address = NULL,
                 .localhostname = NULL,
 
                 .server_expect = SMTP_EXPECT,