From d17eb4faaadbc0f58eeddf03da948a276a717a7a Mon Sep 17 00:00:00 2001
From: Tony Murray <murraytony@gmail.com>
Date: Mon, 3 Sep 2018 01:55:34 -0500
Subject: [PATCH] Do not try to fetch data again if previous attempts failed
 (#9139)

result is null, which will fail isset() check
---
 LibreNMS/Device/YamlDiscovery.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/LibreNMS/Device/YamlDiscovery.php b/LibreNMS/Device/YamlDiscovery.php
index 9456d200f0..7e5a36e0e9 100644
--- a/LibreNMS/Device/YamlDiscovery.php
+++ b/LibreNMS/Device/YamlDiscovery.php
@@ -197,7 +197,7 @@ class YamlDiscovery
 
                     foreach ($data_array as $data) {
                         foreach ((array)$data['oid'] as $oid) {
-                            if (!isset($pre_cache[$oid])) {
+                            if (!array_key_exists($oid, $pre_cache)) {
                                 if (isset($data['snmp_flags'])) {
                                     $snmp_flag = $data['snmp_flags'];
                                 } else {