dns
editdns
editThe DNS filter performs a lookup (either an A record/CNAME record lookup
or a reverse lookup at the PTR record) on records specified under the
reverse
and resolve
arrays.
The config should look like this:
filter { dns { type => 'type' reverse => [ "source_host", "field_with_address" ] resolve => [ "field_with_fqdn" ] action => "replace" } }
This filter, like all filters, only processes 1 event at a time, so the use of this plugin can significantly slow down your pipeline’s throughput if you have a high latency network. By way of example, if each DNS lookup takes 2 milliseconds, the maximum throughput you can achieve with a single filter worker is 500 events per second (1000 milliseconds / 2 milliseconds).
Synopsis
editThis plugin supports the following configuration options:
Required configuration options:
dns { }
Available configuration options:
Setting | Input type | Required | Default value |
---|---|---|---|
string, one of |
No |
|
|
No |
|
||
No |
|
||
No |
|
||
No |
|
||
No |
|
||
No |
|
||
No |
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No |
|||
No |
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No |
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No |
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||
No |
|||
No |
|||
No |
|
Details
edit
action
edit-
Value can be any of:
append
,replace
-
Default value is
"append"
Determine what action to do: append or replace the values in the fields
specified under reverse
and resolve
.
add_field
edit- Value type is hash
-
Default value is
{}
If this filter is successful, add any arbitrary fields to this event.
Field names can be dynamic and include parts of the event using the %{field}
.
Example:
filter { dns { add_field => { "foo_%{somefield}" => "Hello world, from %{host}" } } } [source,ruby] # You can also add multiple fields at once: filter { dns { add_field => { "foo_%{somefield}" => "Hello world, from %{host}" "new_field" => "new_static_value" } } }
If the event has field "somefield" == "hello"
this filter, on success,
would add field foo_hello
if it is present, with the
value above and the %{host}
piece replaced with that value from the
event. The second example would also add a hardcoded field.
add_tag
edit- Value type is array
-
Default value is
[]
If this filter is successful, add arbitrary tags to the event.
Tags can be dynamic and include parts of the event using the %{field}
syntax.
Example:
filter { dns { add_tag => [ "foo_%{somefield}" ] } } [source,ruby] # You can also add multiple tags at once: filter { dns { add_tag => [ "foo_%{somefield}", "taggedy_tag"] } }
If the event has field "somefield" == "hello"
this filter, on success,
would add a tag foo_hello
(and the second example would of course add a taggedy_tag
tag).
failed_cache_ttl
edit- Value type is number
-
Default value is
5
how long to cache failed requests (in seconds)
hit_cache_size
edit- Value type is number
-
Default value is
0
set the size of cache for successful requests
hit_cache_ttl
edit- Value type is number
-
Default value is
60
how long to cache successful requests (in seconds)
max_retries
edit- Value type is number
-
Default value is
2
number of times to retry a failed resolve/reverse
nameserver
edit- Value type is array
- There is no default value for this setting.
Use custom nameserver(s). For example: ["8.8.8.8", "8.8.4.4"]
periodic_flush
edit- Value type is boolean
-
Default value is
false
Call the filter flush method at regular interval. Optional.
remove_field
edit- Value type is array
-
Default value is
[]
If this filter is successful, remove arbitrary fields from this event. Fields names can be dynamic and include parts of the event using the %{field} Example:
filter { dns { remove_field => [ "foo_%{somefield}" ] } } [source,ruby] # You can also remove multiple fields at once: filter { dns { remove_field => [ "foo_%{somefield}", "my_extraneous_field" ] } }
If the event has field "somefield" == "hello"
this filter, on success,
would remove the field with name foo_hello
if it is present. The second
example would remove an additional, non-dynamic field.
remove_tag
edit- Value type is array
-
Default value is
[]
If this filter is successful, remove arbitrary tags from the event.
Tags can be dynamic and include parts of the event using the %{field}
syntax.
Example:
filter { dns { remove_tag => [ "foo_%{somefield}" ] } } [source,ruby] # You can also remove multiple tags at once: filter { dns { remove_tag => [ "foo_%{somefield}", "sad_unwanted_tag"] } }
If the event has field "somefield" == "hello"
this filter, on success,
would remove the tag foo_hello
if it is present. The second example
would remove a sad, unwanted tag as well.
resolve
edit- Value type is array
- There is no default value for this setting.
Forward resolve one or more fields.
reverse
edit- Value type is array
- There is no default value for this setting.
TODO(sissel): The timeout limitation does seem to be fixed in here: http://redmine.ruby-lang.org/issues/5100 # but isn’t currently in JRuby.
TODO(sissel): make action
required? This was always the intent, but it
due to a typo it was never enforced. Thus the default behavior in past
versions was append
by accident.
Reverse resolve one or more fields.