diff --git a/rdma/utils.c b/rdma/utils.c
index aed1a3d0..95b669f3 100644
--- a/rdma/utils.c
+++ b/rdma/utils.c
@@ -56,7 +56,7 @@ bool rd_no_arg(struct rd *rd)
  * mlx5_1/1    | 1          | false
  * mlx5_1/-    | 0          | false
  *
- * In strict mode, /- will return error.
+ * In strict port mode, a non-0 port must be provided
  */
 static int get_port_from_argv(struct rd *rd, uint32_t *port,
 			      bool *is_dump_all, bool strict_port)
@@ -64,7 +64,7 @@ static int get_port_from_argv(struct rd *rd, uint32_t *port,
 	char *slash;
 
 	*port = 0;
-	*is_dump_all = true;
+	*is_dump_all = strict_port ? false : true;
 
 	slash = strchr(rd_argv(rd), '/');
 	/* if no port found, return 0 */
@@ -83,6 +83,9 @@ static int get_port_from_argv(struct rd *rd, uint32_t *port,
 		if (!*port && strlen(slash))
 			return -EINVAL;
 	}
+	if (strict_port && (*port == 0))
+		return -EINVAL;
+
 	return 0;
 }