From dff4879c8c5684768978108ea0d5296b33c68aa3 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Tue, 9 Apr 2024 13:16:52 +0300
Subject: [PATCH] Check if NBD_ATTR_BACKEND_IDENTIFIER is defined

---
 src/nbd_proxy.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/nbd_proxy.cpp b/src/nbd_proxy.cpp
index fad22e36..e82a7892 100644
--- a/src/nbd_proxy.cpp
+++ b/src/nbd_proxy.cpp
@@ -161,12 +161,14 @@ static int netlink_configure(const int *sockfd, int sock_size, int dev_num, uint
         NLA_PUT_U64(msg, NBD_ATTR_DEAD_CONN_TIMEOUT, conn_timeout);
     }
 
+#ifdef NBD_ATTR_BACKEND_IDENTIFIER
     if (backend)
     {
         // Backend is an attribute useful for identication of the device
         // Also it prevents reconfiguration of the device with a different backend string
         NLA_PUT_STRING(msg, NBD_ATTR_BACKEND_IDENTIFIER, backend);
     }
+#endif
 
     msg_attr = nla_nest_start(msg, NBD_ATTR_SOCKETS);
     if (!msg_attr)