Netflow codec plugin
editNetflow codec plugin
edit- Plugin version: v4.3.2
- Released on: 2023-12-22
- 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 "netflow" codec is used for decoding Netflow v5/v9/v10 (IPFIX) flows.
Supported Netflow/IPFIX exporters
editThis codec supports:
- Netflow v5
- Netflow v9
- IPFIX
The following Netflow/IPFIX exporters have been seen and tested with the most recent version of the Netflow Codec:
Netflow exporter | v5 | v9 | IPFIX | Remarks |
---|---|---|---|---|
Barracuda Firewall |
y |
With support for Extended Uniflow |
||
Cisco ACI |
y |
|||
Cisco ASA |
y |
|||
Cisco ASR 1k |
N |
Fails because of duplicate fields |
||
Cisco ASR 9k |
y |
|||
Cisco IOS 12.x |
y |
|||
Cisco ISR w/ HSL |
N |
Fails because of duplicate fields, see: https://github.com/logstash-plugins/logstash-codec-netflow/issues/93 |
||
Cisco WLC |
y |
|||
Citrix Netscaler |
y |
Still some unknown fields, labeled netscalerUnknown<id> |
||
fprobe |
y |
|||
Fortigate FortiOS |
y |
|||
Huawei Netstream |
y |
|||
ipt_NETFLOW |
y |
y |
y |
|
IXIA packet broker |
y |
|||
Juniper MX |
y |
y |
SW > 12.3R8. Fails to decode IPFIX from Junos 16.1 due to duplicate field names which we currently don’t support. |
|
Mikrotik |
y |
y |
||
nProbe |
y |
y |
y |
L7 DPI fields now also supported |
Nokia BRAS |
y |
|||
OpenBSD pflow |
y |
N |
y |
|
Riverbed |
N |
Not supported due to field ID conflicts. Workaround available in the definitions directory over at Elastiflow https://github.com/robcowart/elastiflow |
||
Sandvine Procera PacketLogic |
y |
v15.1 |
||
Softflowd |
y |
y |
y |
IPFIX supported in https://github.com/djmdjm/softflowd |
Sophos UTM |
y |
|||
Streamcore Streamgroomer |
y |
|||
Palo Alto PAN-OS |
y |
|||
Ubiquiti Edgerouter X |
y |
With MPLS labels |
||
VMware VDS |
y |
Still some unknown fields |
||
YAF |
y |
With silk and applabel, but no DPI plugin support |
||
vIPtela |
y |
Usage
editExample Logstash configuration that will listen on 2055/udp for Netflow v5,v9 and IPFIX:
input { udp { port => 2055 codec => netflow } }
For high-performance production environments the configuration below will decode up to 15000 flows/sec from a Cisco ASR 9000 router on a dedicated 16 CPU instance. If your total flowrate exceeds 15000 flows/sec, you should use multiple Logstash instances.
Note that for richer flows from a Cisco ASA firewall this number will be at least 3x lower.
input { udp { port => 2055 codec => netflow receive_buffer_bytes => 16777216 workers => 16 }
To mitigate dropped packets, make sure to increase the Linux kernel receive buffer limit:
# sysctl -w net.core.rmem_max=$((1024*1024*16))
Netflow Codec Configuration Options
editSetting | Input type | Required |
---|---|---|
a valid filesystem path |
No |
|
No |
||
No |
||
a valid filesystem path |
No |
|
a valid filesystem path |
No |
|
No |
||
No |
cache_save_path
edit- Value type is path
- There is no default value for this setting.
Enables the template cache and saves it in the specified directory. This minimizes data loss after Logstash restarts because the codec doesn’t have to wait for the arrival of templates, but instead reload already received templates received during previous runs.
Template caches are saved as:
cache_ttl
edit- Value type is number
-
Default value is
4000
Netflow v9/v10 template cache TTL (seconds)
include_flowset_id
edit- Value type is boolean
-
Default value is
false
Only makes sense for ipfix, v9 already includes this Setting to true will include the flowset_id in events Allows you to work with sequences, for instance with the aggregate filter
ipfix_definitions
edit- Value type is path
- There is no default value for this setting.
Override YAML file containing IPFIX field definitions
Very similar to the Netflow version except there is a top level Private Enterprise Number (PEN) key added:
pen: id: - :uintN or :ip4_addr or :ip6_addr or :mac_addr or :string - :name id: - :skip
There is an implicit PEN 0 for the standard fields.
See https://github.com/logstash-plugins/logstash-codec-netflow/blob/master/lib/logstash/codecs/netflow/ipfix.yaml for the base set.
netflow_definitions
edit- Value type is path
- There is no default value for this setting.
Override YAML file containing Netflow field definitions
Each Netflow field is defined like so:
id: - default length in bytes - :name id: - :uintN or :ip4_addr or :ip6_addr or :mac_addr or :string - :name id: - :skip
See https://github.com/logstash-plugins/logstash-codec-netflow/blob/master/lib/logstash/codecs/netflow/netflow.yaml for the base set.