SNMP trap input plugin
editSNMP trap input plugin
edit- A component of the snmp integration plugin
- Integration version: v4.0.4
- Released on: 2024-07-08
- Changelog
For other versions, see the Versioned plugin docs.
Getting help
editFor questions about the plugin, open a topic in the Discuss forums. For bugs or feature requests, open an issue in Github. For the list of Elastic supported plugins, please consult the Elastic Support Matrix.
Description
editThe logstash-input-snmptrap
plugin reads SNMP trap messages as events.
Resulting message
field resembles:
{"agent_addr":"192.168.1.40", "generic_trap":6, "specific_trap":15511, "enterprise":"1.3.6.1.2.1.1.1", "variable_bindings":{"1.3.6.1.2.1.1.2.0":"test one", "1.3.6.1.2.1.1.1.0":"test two"}, "type":"V1TRAP", "community":"public", "version":1, "timestamp":1500}
Event Metadata and the Elastic Common Schema (ECS)
editBecause SNMP data has specific field names based on OIDs, we recommend setting a target
.
The source host field changes based on ecs_compatibility
.
ECS disabled |
ECS v1, v8 |
Availability |
Description |
[host] |
[host][ip] |
Always |
IP address of the host e.g. "192.168.1.11" |
This plugin also adds the trap PDU metadata to each event.
The value is stored in the @metadata
where it can be used by other plugins in the pipeline.
ECS disabled, v1, v8 |
Availability |
Description |
[@metadata][input][snmptrap][pdu][agent_addr] |
|
Network address of the object generating the trap |
[@metadata][input][snmptrap][pdu][community] |
|
SNMP community |
[@metadata][input][snmptrap][pdu][enterprise] |
|
Type of object generating the trap |
[@metadata][input][snmptrap][pdu][error_index] |
|
Provides additional information by identifying which variable binding in the list caused the error |
[@metadata][input][snmptrap][pdu][error_status] |
|
Error status code |
[@metadata][input][snmptrap][pdu][error_status_text] |
|
Error status code description |
[@metadata][input][snmptrap][pdu][generic_trap] |
|
Generic trap type |
[@metadata][input][snmptrap][pdu][request_id] |
|
Request ID |
[@metadata][input][snmptrap][pdu][specific_trap] |
|
Specific code, presented even if the generic_trap is not enterprise specific |
[@metadata][input][snmptrap][pdu][timestamp] |
|
Time elapsed between the last (re)initialization of the network entity and the generation of the trap |
[@metadata][input][snmptrap][pdu][type] |
Always |
PDU type |
[@metadata][input][snmptrap][pdu][variable_bindings] |
Always |
SNMP variable bindings values |
[@metadata][input][snmptrap][pdu][version] |
Always |
SNMP version |
Importing MIBs
editThis plugin already includes the IETF MIBs (management information bases), and you do not need to import them. If you need additional MIBs, you need to import them. Check out Importing MIBs for info.
SNMP Trap Input Configuration Options
editThis plugin supports the following configuration options plus the Common options described later.
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
string, one of |
No |
|
Yes |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
Deprecated |
SNMPv3 Authentication Options
editThis plugin supports the following SNMPv3 authentication options.
SNMP Trap Input Configuration Options
editAlso see Common options for a list of options supported by all input plugins.
community
edit- Value type is array
-
Default value is
["public"]
The SNMPv1 and SNMPv2c communities to listen for.
To allow any community, set this config value to empty community => []
.
Examples
Listen for public
and guest
communities
input { snmptrap { community => ["public", "guest"] } }
Listen for all communities
input { snmptrap { community => [] } }
ecs_compatibility
edit- Value type is string
-
Supported values are:
-
disabled
: does not use ECS-compatible field names (fields might be set at the root of the event) -
v1
,v8
: avoids field names that might conflict with Elastic Common Schema (for example, thehost
field)
-
-
Default value depends on which version of Logstash is running:
-
When Logstash provides a
pipeline.ecs_compatibility
setting, its value is used as the default -
Otherwise, the default value is
disabled
.
-
When Logstash provides a
Controls this plugin’s compatibility with the Elastic Common Schema (ECS).
mib_paths
edit- Value type is path
- There is no default value for this setting
The mib_paths
option specifies the location of one or more imported MIB files.
The value can be either a dir path containing the imported MIB (.dic
, .yaml
) files or a
file path to a single MIB file.
oid_mapping_format
edit-
Value can be any of:
default
,ruby_snmp
,dotted_string
-
Default value is
"default"
Defines the mapping textual representation of an OID in the Logstash event:
* default
translates every identifier, using the MIBs resolved names, separated by dots. Example:
1.3.6.1.2.1.1.2.0
is mapped as iso.org.dod.internet.mgmt.mib-2.system.sysObjectID.0
* ruby_snmp
produces field names prefixed by the MIBs module name, followed by the latest resolved identifier name and unknowns values. Example:
1.3.6.1.2.1.1.2.0
is mapped as SNMPv2-MIB::sysObjectID.0
.
* dotted_string
maps fields using the standard dotted string representation, Example:
1.3.6.1.2.1.1.2.0
is mapped as 1.3.6.1.2.1.1.2.0
oid_map_field_values
edit- Value type is boolean
-
Default value is
false
Defines if the Logstash event fields values, which types are OID
, are mapped using the configured OID textual representation
set on the oid_mapping_format
option.
oid_root_skip
edit- Value type is number
-
Default value is
0
The oid_root_skip
option specifies the number of OID root digits to ignore in the event field name.
For example, in a numeric OID like "1.3.6.1.2.1.1.1.0" the first 5 digits could be ignored by setting oid_root_skip => 5
which would result in a field name "1.1.1.0". Similarly when a MIB is used an OID such
"1.3.6.1.2.mib-2.system.sysDescr.0" would become "mib-2.system.sysDescr.0"
-
You can use this setting or
oid_path_length
, but not both at the same time. -
Use this setting only if
oid_mapping_format
is set todefault
.
oid_path_length
edit- Value type is number
-
Default value is
0
The oid_path_length
option specifies the number of OID root digits to retain in the event field name.
For example, in a numeric OID like "1.3.6.1.2.1.1.1.0" the last 2 digits could be retained by setting oid_path_length => 2
which would result in a field name "1.0". Similarly when a MIB is used an OID such
"1.3.6.1.2.mib-2.system.sysDescr.0" would become "sysDescr.0"
-
You can use this setting or
oid_root_skip
, but not both at the same time. -
Use this setting only if
oid_mapping_format
is set todefault
.
port
edit- Value type is number
-
Default value is
1062
The port to listen on. Remember that ports less than 1024 (privileged ports) may require root to use. hence the default of 1062.
supported_transports
edit- Value type is string
-
Allowed values are:
tcp
,udp
-
Default value is
["udp"]
The supported transport protocols to listen on.
SNMP was originally designed for use with UDP as transport protocol and is the official recommendation. TCP is an optional transport mapping and can be enabled if needed. For more details on SNMP over TCP, please refer to the RFC-3430.
supported_versions
edit- Value type is string
-
Allowed values are:
1
,2c
,3
-
Default value is
["1", "2c"]
The supported SNMP protocol versions to listen on. SNMP messages for versions that are either unsupported and/or disabled are automatically discarded.
target
edit- Value type is string
- There is no default value for this setting
The name of the field under which SNMP payloads are assigned. If not specified data will be stored in the root of the event.
Setting a target is recommended when ecs_compatibility
is enabled.
threads
edit- Value type is number
- Default value is 75% of the number of CPU cores
The number of threads to use for processing the received SNMP trap messages.
use_provided_mibs
edit- Value type is boolean
-
Default value is
true
This plugin provides all IETF MIBs (management information bases), publicly available in the libsmi version 0.5.0
.
When enabled, it automatically loads the bundled MIBs and provides mapping of the numeric OIDs to MIB field names in the resulting event.
SNMPv3 Authentication Options
editA single user can be configured. Multiple snmptrap input declarations will be needed if multiple SNMPv3 users are required. These options are required only if you are using SNMPv3.
auth_pass
edit- Value type is password
- There is no default value for this setting
The auth_pass
option specifies the SNMPv3 authentication passphrase or password.
auth_protocol
editThe auth_protocol
option specifies the SNMPv3 authentication protocol or type
-
Value can be any of:
md5
,sha
,sha2
,hmac128sha224
,hmac192sha256
,hmac256sha384
,hmac384sha512
-
Note that
sha2
andhmac192sha256
are equivalent - There is no default value for this setting
priv_pass
edit- Value type is password
- There is no default value for this setting
The priv_pass
option specifies the SNMPv3 encryption password.
priv_protocol
edit-
Value can be any of:
des
,3des
,aes
,aes128
,aes192
,aes256
-
Note that
aes
andaes128
are equivalent - There is no default value for this setting
The priv_protocol
option specifies the SNMPv3 privacy/encryption protocol.
security_level
edit-
Value can be any of:
noAuthNoPriv
,authNoPriv
,authPriv
- There is no default value for this setting
The security_level
option specifies the SNMPv3 security level between
Authentication, No Privacy; Authentication, Privacy; or no Authentication, no Privacy.
Configuration examples
editSpecifying SNMPv3 traps settings
input { snmptrap { supported_versions => ['3'] security_name => "mySecurityName" auth_protocol => "sha" auth_pass => "ShaPassword" priv_protocol => "aes" priv_pass => "AesPasword" security_level => "authPriv" } }
Common options
editThese configuration options are supported by all input plugins:
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
No |
||
No |
codec
edit- Value type is codec
-
Default value is
"plain"
The codec used for input data. Input codecs are a convenient method for decoding your data before it enters the input, without needing a separate filter in your Logstash pipeline.
enable_metric
edit- Value type is boolean
-
Default value is
true
Disable or enable metric logging for this specific plugin instance by default we record all the metrics we can, but you can disable metrics collection for a specific plugin.
id
edit- Value type is string
- There is no default value for this setting.
Add a unique ID
to the plugin configuration. If no ID is specified, Logstash will generate one.
It is strongly recommended to set this ID in your configuration. This is particularly useful
when you have two or more plugins of the same type, for example, if you have 2 snmptrap inputs.
Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.
input { snmptrap { id => "my_plugin_id" } }
Variable substitution in the id
field only supports environment variables
and does not support the use of values from the secret store.
tags
edit- Value type is array
- There is no default value for this setting.
Add any number of arbitrary tags to your event.
This can help with processing later.
type
edit- Value type is string
- There is no default value for this setting.
Add a type
field to all events handled by this input.
Types are used mainly for filter activation.
The type is stored as part of the event itself, so you can also use the type to search for it in Kibana.
If you try to set a type on an event that already has one (for example when you send an event from a shipper to an indexer) then a new input will not override the existing type. A type set at the shipper stays with that event for its life even when sent to another Logstash server.