added oids.no_bulk os setting (#13666)

* forcewalk param

* [snmp][no_bulk]

* var names, test, schema

* Key off OIDs, not mibs

luminato is POC and needs to be reverted before merge.

* fix up os schema

* docs

* remove luminato arbitrary changes

Co-authored-by: Tony Murray <murraytony@gmail.com>

LibreNMS/Data/Source/NetSnmpQuery.php

@@ -269,7 +269,7 @@ class NetSnmpQuery implements SnmpQueryInterface
 
     private function buildCli(string $command, array $oids): array
     {
-        $cmd = $this->initCommand($command);
+        $cmd = $this->initCommand($command, $oids);
 
         array_push($cmd, '-M', $this->mibDirectories());
 
@@ -349,9 +349,13 @@ class NetSnmpQuery implements SnmpQueryInterface
         return new SnmpResponse($output, $stderr, $exitCode);
     }
 
-    private function initCommand(string $binary): array
+    private function initCommand(string $binary, array $oids): array
     {
-        if ($binary == 'snmpwalk' && $this->device->snmpver !== 'v1' && Config::getOsSetting($this->device->os, 'snmp_bulk', true)) {
+        if ($binary == 'snmpwalk'
+            && $this->device->snmpver !== 'v1'
+            && Config::getOsSetting($this->device->os, 'snmp_bulk', true)
+            && empty(array_intersect($oids, Config::getCombined($this->device->os, 'oids.no_bulk'))) // skip for oids that do not work with bulk
+        ) {
             $snmpcmd = [Config::get('snmpbulkwalk', 'snmpbulkwalk')];
 
             $max_repeaters = $this->device->getAttrib('snmp_max_repeaters') ?: Config::getOsSetting($this->device->os, 'snmp.max_repeaters', Config::get('snmp.max_repeaters', false));

doc/Developing/os/Settings.md

@@ -122,6 +122,15 @@ snmpwalk for an OS set the following.
 snmp_bulk: false
 ```
 
+If only some specific OIDs fail with snmpbulkwalk. You can disable just those OIDs.
+This needs to match exactly the OID being walked by LibreNMS. MIB::oid is preferred to prevent name collisions.
+
+```yaml
+oids:
+    no_bulk:
+        - UCD-SNMP-MIB::laLoadInt
+```
+
 #### Limit the oids per snmpget
 
 ```yaml

includes/snmp.inc.php

@@ -130,7 +130,10 @@ function gen_snmpget_cmd($device, $oids, $options = null, $mib = null, $mibdir =
  */
 function gen_snmpwalk_cmd($device, $oids, $options = null, $mib = null, $mibdir = null)
 {
-    if ($device['snmpver'] == 'v1' || (isset($device['os']) && Config::getOsSetting($device['os'], 'snmp_bulk', true) == false)) {
+    if ($device['snmpver'] == 'v1'
+        || (isset($device['os']) && (Config::getOsSetting($device['os'], 'snmp_bulk', true) == false
+                || ! empty(array_intersect(Arr::wrap($oids), Config::getCombined($device['os'], 'oids.no_bulk'))))) // skip for oids that do not work with bulk
+    ) {
         $snmpcmd = [Config::get('snmpwalk')];
     } else {
         $snmpcmd = [Config::get('snmpbulkwalk')];

misc/config_definitions.json

@@ -5145,6 +5145,13 @@
             "type": "integer",
             "default": 0
         },
+        "snmp.oids.no_bulk": {
+            "group": "poller",
+            "section": "snmp",
+            "order": 20,
+            "type": "array",
+            "default": null
+        },
         "snmp.timeout": {
             "group": "poller",
             "section": "snmp",

misc/os_schema.json

@@ -363,6 +363,15 @@
                 "type": "string"
             }
         },
+        "oids": {
+            "type": "object",
+            "properties": {
+                "no_bulk": {
+                    "type": "array"
+                }
+            },
+            "additionalProperties": false
+        },
         "snmp_bulk": {
             "type": "boolean"
         },

resources/lang/en/settings.php

@@ -1367,6 +1367,12 @@ return [
                 'description' => 'Max Repeaters',
                 'help' => 'Set repeaters to use for SNMP bulk requests',
             ],
+            'oids' => [
+                'no_bulk' => [
+                    'description' => 'Disable snmp bulk for OIDs',
+                    'help' => 'Disable snmp bulk operation for certain OIDs. Generally, this should be set on an OS instead. Format should be MIB::OID',
+                ],
+            ],
             'port' => [
                 'description' => 'Port',
                 'help' => 'Set the tcp/udp port to be used for SNMP',