SNMP input plugin
editSNMP 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 SNMP input polls network devices using Simple Network Management Protocol (SNMP) to gather information related to the current state of the devices operation.
The SNMP input plugin supports SNMP v1, v2c, and v3 over UDP and TCP transport protocols.
Compatibility with the Elastic Common Schema (ECS)
editBecause SNMP data has specific field names based on OIDs, we recommend setting a target
.
Metadata fields follow a specific naming convention when ECS compatibility mode is enabled.
ECS disabled |
ECS v1, v8 |
Description |
[@metadata][host_protocol] |
[@metadata][input][snmp][host][protocol] |
The protocol used to retrieve data e.g. "udp" |
[@metadata][host_address] |
[@metadata][input][snmp][host][address] |
The host IP e.g. "192.168.1.1" |
[@metadata][host_port] |
[@metadata][input][snmp][host][port] |
The host’s port e.g. "161" |
[@metadata][host_community] |
[@metadata][input][snmp][host][community] |
The configured community e.g. "public" |
[host] |
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 Input Configuration Options
editThis plugin supports the following configuration options plus the Common options described later.
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
string, one of |
No |
|
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
SNMPv3 Authentication Options
editThis plugin supports the following SNMPv3 authentication options.
SNMP Input Configuration Options
editAlso see Common options for a list of options supported by all input plugins.
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).
get
edit- Value type is array
- There is no default value for this setting
Use the get
option to query for scalar values for the given OID(s).
One or more OID(s) are specified as an array of strings of OID(s).
Example
input { snmp { get => ["1.3.6.1.2.1.1.1.0", "1.3.6.1.2.1.1.3.0", "1.3.6.1.2.1.1.5.0"] hosts => [{host => "udp:127.0.0.1/161" community => "public"}] } }
hosts
edit- Value type is array
- There is no default value for this setting
The hosts
option specifies the list of hosts to query the configured get
and walk
options.
Each host definition is a hash and must define the host
key and value.
host
must use the format {tcp|udp}:{ip address}/{port}
, for example host => "udp:127.0.0.1/161"
Each host definition can optionally include the following keys and values:
-
community
the community string, default ispublic
. -
version
1
,2c
or3
, default is2c
. -
retries
is the number of retries in case of failure, default is2
. -
timeout
is the timeout in milliseconds with a default value of1000
.
Specifying all hosts options
input { snmp { get => ["1.3.6.1.2.1.1.1.0"] hosts => [{host => "udp:127.0.0.1/161" community => "public" version => "2c" retries => 2 timeout => 1000}] } }
Specifying multiple hosts
input { snmp { get => ["1.3.6.1.2.1.1.1.0"] hosts => [{host => "udp:127.0.0.1/161" community => "public"}, {host => "udp:192.168.0.1/161" community => "private"}] } }
Specifying IPv6 hosts
input { snmp { get => ["1.3.6.1.2.1.1.1.0"] hosts => [{host => "udp:[::1]/161" community => "public"}, {host => "udp:[2001:db8::2:1]/161" community => "private"}] } }
interval
edit- Value type is number
-
Default value is
30
The interval
option specifies the polling interval in seconds.
If polling all configured hosts takes longer than this interval, a warning will be emitted to the logs.
local_engine_id
edit- Value type is string
- There is no default value for this setting
The SNMPv3 local engine ID. Its length must be greater or equal than 5 and less or equal than 32. If not provided, a default ID is generated based on the local IP address and additional four random bytes.
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.
This plugin includes the IETF MIBs. If you require other MIBs, you need to import them. See Importing MIBs.
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 asiso.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 asSNMPv2-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 as1.3.6.1.2.1.1.2.0
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. -
This setting can be used only if
oid_mapping_format
is set todefault
.
poll_hosts_timeout
edit- Value type is number
- There is no default value for this setting
Specifies the maximum amount of time in milliseconds the polling client will wait for all hosts
responses.
If all responses are not received before the timeout elapses, the client will fail and some hosts might not get polled during the current cycle.
By default, it uses the highest value between 1 hour
, the maximum hosts
configured timeout
,
and the interval
value.
walk
edit- Value type is array
- There is no default value for this setting
Use the walk
option to retrieve the subtree of information for the given OID(s).
One or more OID(s) are specified as an array of strings of OID(s).
Queries the subtree of information starting at the given OID(s).
Example
snmp { walk => ["1.3.6.1.2.1.1"] hosts => [{host => "udp:127.0.0.1/161" community => "public"}] } }
tables
edit- Value type is array
- There is no default value for this setting
- Results are returned under a field using the table name
The tables
option is used to query for tabular values for the given column OID(s).
Each table definition is a hash and must define the name key and value and the columns to return.
Specifying a single table
input { snmp { hosts => [{host => "udp:127.0.0.1/161" community => "public" version => "2c" retries => 2 timeout => 1000}] tables => [ {"name" => "interfaces" "columns" => ["1.3.6.1.2.1.2.2.1.1", "1.3.6.1.2.1.2.2.1.2", "1.3.6.1.2.1.2.2.1.5"]} ] } }
Specifying multiple tables
input { snmp { get => ["1.3.6.1.2.1.1.1.0"] tables => [ {"name" => "interfaces" "columns" => ["1.3.6.1.2.1.2.2.1.1", "1.3.6.1.2.1.2.2.1.2", "1.3.6.1.2.1.2.2.1.5"]}, {"name" => "ltmPoolStatTable" "columns" => ["1.3.6.1.4.1.3375.2.2.5.2.3.1.1", "1.3.6.1.4.1.3375.2.2.5.2.3.1.6"]} ] } }
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 the number of CPU cores
The number of threads to use for executing the hosts SNMP requests.
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 and will be used for all defined SNMPv3 hosts. Multiple snmp 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 settings
input { snmp { hosts => [{host => "udp:127.0.0.1/161" version => "3"}] get => ["1.3.6.1.2.1.1.1.0"] security_name => "mySecurityName" auth_protocol => "sha" auth_pass => "ShaPassword" priv_protocol => "aes" priv_pass => "AesPasword" security_level => "authPriv" } }
Using both get
and walk
in the same poll cycle for each host(s)
input { snmp { get => ["1.3.6.1.2.1.1.1.0", "1.3.6.1.2.1.1.3.0", "1.3.6.1.2.1.1.5.0"] walk => ["1.3.6.1.2.1.1"] hosts => [{host => "udp:127.0.0.1/161" community => "public"}] } }
Specifying all global options
input { snmp { get => ["1.3.6.1.2.1.1.1.0"] hosts => [{host => "udp:127.0.0.1/161"}] mib_paths => ["path/to/converted/mibfile.dic"] oid_root_skip => 0 interval => 30 } }
Polled host information
editAll the polled host information is stored in the event @metadata
:
-
[@metadata][host_protocol]
:udp
ortcp
-
[@metadata][host_address]
: host address for example127.0.0.1
-
[@metadata][host_port]
: host port (for example161
) -
[@metadata][host_community]
: community string for examplepublic
By default, a host
field is added to the event with the [@metadata][host_address]
value.
config :add_field, :validate => :hash, :default => { "host" => "%{[@metadata][host_address]}" }
You can customize the format and content of the host
field by specifying an alternate add_field
.
Example
input { snmp { get => ["1.3.6.1.2.1.1.1.0"] hosts => [{host => "udp:127.0.0.1/161"}] add_field => {host => "%{[@metadata][host_protocol]}:%{[@metadata][host_address]}/%{[@metadata][host_port]},%{[@metadata][host_community]}"} } }
Common options
editThese configuration options are supported by all input plugins:
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
No |
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 snmp inputs.
Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.
input { snmp { 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.