Raijin (om_raijin)
This module enables logs to be forwarded to Raijin Database servers for ingestion. It connects to the URL specified in the configuration in either HTTP or HTTPS mode. Raijin accepts HTTP POST requests with multiple JSON records in the request body, assuming that there is a target database table already created on the Raijin side. Although Raijin accepts structured data in flat JSON (i.e. a list of key-value pairs) format, it does not support JSON values comprised of nested data structures or other non-scalar data such as arrays and maps. Raijin currently does not support authorization/SSL but the om_raijin module supports TLS since TLS can be enabled with an HTTP proxy.
This module requires the xm_json extension module to be loaded in order to convert the payload to JSON. See the Output log format section for information on the format of the payload. |
Output log format
om_raijin forwards log records over HTTP(S) as JSON payload.
The JSON format depends on the value of the $raw_event
field.
The module checks if the value of $raw_event
is valid JSON and applies the following rules:
-
If it is valid JSON, the value is forwarded as is.
-
If it is not valid JSON, the log record is converted to JSON in the following format:
{ "raw_event": "<json_escaped_raw_event>" }
Additional metadata, including the NXLog-specific fields EventReceivedTime
, SourceModuleName
, and SourceModuleType
, will not be included in the output unless these values have been written to the $raw_event
field.
The processing required to achieve this depends on the format of the input data, but generally it means you need to:
-
Parse the log record according to the data format.
-
If the input data is already in JSON format, use parse_json() to parse
$raw_event
into fields. -
If the input is unstructured plain text data, copy the value of
$raw_event
to a custom field.
-
-
Create and populate any additional custom fields.
-
Use to_json() to convert the fields to JSON format and update the value of
$raw_event
.
See the Examples section for NXLog configuration examples of the above.
Configuration
The om_raijin module accepts the following directives in addition to the common module directives.
These three om_raijin directives are required:
- DBName
-
This mandatory directive specifies the name of the Raijin database containing the table where logs will be stored.
- DBTable
-
This mandatory directive specifies the name of the database table where log events will be inserted as JSON records.
- URL
-
This mandatory directive is comprised of the REST API URI that Raijin Server uses for receiving bulk, JSON-formatted events via POST requests:
http://<RaijinServerHostname>:<port>
If an om_raijin module instance contains multiple URL directives, the hosts will function as a cluster in NXLog failover mode. This directive also supports HTTPS URLs. If the optional port number part of the URL (
:<port>
) is not explicitly included in the URL, it will default to port 80 for HTTP (or port 443 for HTTPS).
The Raijin Database REST API listens by default on port 2500. If you plan to use this directive without explicitly specifying a port number, make sure the Raijin Database server is configured to listen on the correct default port corresponding to this directive (either 80 or 443). |
The following om_raijin directives are optional.
- FlushInterval
-
This directive has been deprecated. See Batch processing for details.
- FlushLimit
-
This directive has been deprecated. See Batch processing for details.
- HTTPSAllowUntrusted
-
Accepts a boolean value to determine whether the remote connection should be allowed without certificate verification. If set to
TRUE
, the connection will be allowed even if the remote HTTPS server presents an unknown or self-signed certificate. The default value isFALSE
; the remote HTTPS server must present a trusted certificate.
- HTTPBasicAuthUser
-
HTTP basic authorization username.
- HTTPBasicAuthPassword
-
HTTP basic authorization password.
HTTP authorization works only when both parameters are set. |
- HTTPSCADir
-
This directive specifies a path to a directory containing certificate authority (CA) certificates. These certificates will be used to verify the certificate presented by the remote server. The certificate files must be named using the OpenSSL hashed format, i.e. the hash of the certificate followed by .0, .1 etc. To find the hash of a certificate using OpenSSL:
$ openssl x509 -hash -noout -in ca.crt
For example, if the certificate hash is
e2f14e4a
, then the certificate filename should bee2f14e4a.0
. If there is another certificate with the same hash then it should be namede2f14e4a.1
and so on.A remote server’s self-signed certificate (which is not signed by a CA) can also be trusted by including a copy of the certificate in this directory.
The default operating system root certificate store will be used if this directive is not specified. Unix-like operating systems commonly store root certificates in
/etc/ssl/certs
. Windows operating systems use the Windows Certificate Store, while macOS uses the Keychain Access Application as the default certificate store. See NXLog TLS/SSL configuration in the User Guide for more information on using this directive.
- HTTPSCAFile
-
This specifies the path of the certificate authority (CA) certificate that will be used to verify the certificate presented by the remote server. A remote server’s self-signed certificate (which is not signed by a CA) can be trusted by specifying the remote server certificate itself. In case of certificates signed by an intermediate CA, the certificate specified must contain the complete certificate chain (certificate bundle).
- HTTPSCertFile
-
Specifies the path of the certificate file to be used for the HTTPS handshake.
- HTTPSCertKeyFile
-
Specifies the path of the certificate key file to be used for the HTTPS handshake.
- HTTPSCRLDir
-
Specifies the path to a directory containing certificate revocation lists (CRLs), which will be consulted when checking the certificate of the remote HTTPS server. The certificate filenames in this directory must be in the OpenSSL hashed format.
- HTTPSCRLFile
-
Specifies the path of the certificate revocation list (CRL) which will be consulted when checking the certificate of the remote HTTPS server.
- HTTPSKeyPass
-
Specifies a password for the certificate key file defined in HTTPSCertKeyFile. This directive is not needed for passwordless private keys.
- HTTPSSSLCipher
-
Sets the permitted SSL cipher list, overriding the default. Use the format described in the ciphers man page.
- HTTPSSSLCiphersuites
-
This optional directive can be used to set the permitted cipher list for TLSv1.3. Use the same format as in the HTTPSSSLCipher directive. Refer to the OpenSSL documentation for a list of valid TLS v1.3 cipher suites. The default value is:
TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256
- HTTPSSSLCompression
-
Accepts a boolean value to determine whether data compression should be enabled. The compression algorithm is based on the zlib compression library. If not specified, it defaults to
FALSE
(compression will be disabled).
Some Linux packages (for example, Debian) use the OpenSSL library provided by the OS and may not support the zlib compression mechanism. The module will emit a warning on startup if compression support is missing. The generic deb/rpm packages are bundled with a zlib-enabled libssl library. |
- HTTPSSSLProtocol
-
This directive can be used to set the allowed SSL/TLS protocol(s). It takes a comma-separated list of values which can be any of the following:
SSLv2
,SSLv3
,TLSv1
,TLSv1.1
,TLSv1.2
andTLSv1.3
. By default, theTLSv1.2
andTLSv1.3
protocols are allowed. Note that the OpenSSL library shipped by Linux distributions may not supportSSLv2
andSSLv3
, and these will not work even if enabled with this directive.
- LocalPort
-
This optional directive specifies the local port number of the connection. If this is not specified, a random high port number will be used, which is not always ideal in firewalled network environments.
Due to the required
TIME-WAIT
delay in closing connections, attempts to bind toLocalPort
may fail. In such cases, the messageAddress already in use
will be written tonxlog.log
. If the situation persists, it could impede network performance.
- ProxyAddress
-
Specifies the IP address of the proxy server in case the module needs to connect to a Raijin Database server through a proxy.
The om_raijin module supports only HTTP proxies, i.e. SOCKS4/SOCKS5 proxies are not supported. |
- ProxyPort
-
Specifies the port number required to connect to the proxy server.
- Reconnect
-
This optional directive sets the reconnect interval in seconds. If it is set, the module attempts to reconnect in every defined second. If it is not set, the reconnect interval will start at 1 second and doubles with every attempt. If the duration of the successful connection is greater than the current reconnect interval, then the reconnect interval will be reset to 1 sec.
The Reconnect directive must be used with caution. If it is used on multiple systems, it can send reconnect requests simultaneously to the same destination, potentially overloading the destination system. It may also cause NXLog to use unusually high system resources or cause NXLog to become unresponsive.
- SNI
-
This optional directive specifies the hostname used for Server Name Indication (SNI) in HTTPS mode. If not specified, it defaults to the hostname in the URL directive.
Procedures
The following procedures are exported by om_raijin.
reconnect();
-
Force a reconnection. This can be used from a Schedule block to periodically reconnect to the server.
The reconnect() procedure must be used with caution. If configured, it can attempt to reconnect after every event sent, potentially overloading the destination system.
Examples
This configuration reads log messages from a file and forwards them to a Raijin Database server deployed on localhost
.
No further processing is done on the log records.
<Extension json>
Module xm_json
</Extension>
<Input file>
Module im_file
File '/var/log/myapp*.log'
</Input>
<Output raijin_local>
Module om_raijin
URL http://localhost:2500
DBName logdb
DBTable logs
</Output>
The following is a log record sample read by NXLog.
Mar 24 15:58:53 pc1 systemd[1452]: tracker-store.service: Succeeded.
The following is the JSON-formatted log record that will be sent to the Raijin Database server.
{
"raw_event": "Mar 24 15:58:53 pc1 systemd[1452]: tracker-store.service: Succeeded."
}
This configuration reads log records from file and adds a $Hostname
metadata field.
Log records are converted to JSON using the to_json() procedure of the xm_json module before they are forwarded to the Raijin Database server.
<Extension json>
Module xm_json
</Extension>
<Input file>
Module im_file
File '/var/log/myapp*.log'
Exec $Hostname = hostname();
Exec $Message = $raw_event;
</Input>
<Output raijin_local>
Module om_raijin
URL http://localhost:2500
DBName logdb
DBTable logs
Exec to_json();
</Output>
The following is a log record sample read by NXLog.
Mar 24 15:58:53 pc1 systemd[1452]: tracker-store.service: Succeeded.
The following is the JSON-formatted log record that will be sent to the Raijin Database server.
{
"EventReceivedTime": "2021-03-24T16:52:20.457348+01:00",
"SourceModuleName": "file",
"SourceModuleType": "im_file",
"Hostname": "pc1",
"Message": "Mar 24 15:58:53 pc1 systemd[1452]: tracker-store.service: Succeeded."
}
This configuration reads syslog records from file. It uses the parse_syslog() procedure of the xm_syslog module to parse logs into structured data. Log records are then converted to JSON using the to_json() procedure of the xm_json module before they are forwarded to the Raijin Database server.
<Extension syslog>
Module xm_syslog
</Extension>
<Extension json>
Module xm_json
</Extension>
<Input file>
Module im_file
File '/var/log/myapp*.log'
Exec parse_syslog();
</Input>
<Output raijin_local>
Module om_raijin
URL http://localhost:2500
DBName logdb
DBTable logs
Exec to_json();
</Output>
The following is a log record sample read by NXLog.
Mar 24 15:58:53 pc1 systemd[1452]: tracker-store.service: Succeeded.
The following is the JSON-formatted log record that will be sent to the Raijin Database server.
{
"EventReceivedTime": "2021-03-24T16:30:18.920342+01:00",
"SourceModuleName": "file",
"SourceModuleType": "im_file",
"SyslogFacilityValue": 1,
"SyslogFacility": "USER",
"SyslogSeverityValue": 5,
"SyslogSeverity": "NOTICE",
"SeverityValue": 2,
"Severity": "INFO",
"Hostname": "pc1",
"EventTime": "2021-03-24T15:58:53.000000+01:00",
"SourceName": "systemd",
"ProcessID": 1452,
"Message": "tracker-store.service: Succeeded."
}
This configuration reads JSON-formatted log records from file.
It uses the parse_json() procedure of the xm_json module to parse logs into structured data and adds an $EventType
metadata field.
Log records are then converted back to JSON using the to_json() procedure before they are forwarded to the Raijin Database server.
<Extension json>
Module xm_json
</Extension>
<Input file>
Module im_file
File '/var/log/myapp*.log'
Exec parse_json();
Exec $EventType = "browser-history";
</Input>
<Output raijin_local>
Module om_raijin
URL http://localhost:2500
DBName logdb
DBTable logs
Exec to_json();
</Output>
The following is a log record sample read by NXLog.
{
"AccessTime": "2021-03-24T16:30:43.000000+01:00",
"URL": "https://nxlog.co",
"Title": "High Performance Log Collection Solutions",
"Username": "user1"
}
The following is the JSON-formatted log record that will be sent to the Raijin Database server.
{
"EventReceivedTime": "2021-03-24T17:14:23.908155+01:00",
"SourceModuleName": "file",
"SourceModuleType": "im_file",
"AccessTime": "2021-03-24T16:30:43.000000+01:00",
"URL": "https://nxlog.co",
"Title": "High Performance Log Collection Solutions",
"Username": "user1",
"EventType": "browser-history"
}
This configuration sends logs to a cluster of Raijin Database servers
configured for NXLog failover mode. The cluster is
comprised of three hosts:
http://raijin-1.example.com:2500
, http://localhost:2500
, and
http://192.168.1.123:2500
.
<Extension json>
Module xm_json
</Extension>
<Output raijin_cluster>
Module om_raijin
URL http://raijin-1.example.com:2500
URL http://localhost:2500
URL http://192.168.1.123:2500
DBName logdb
DBTable logs
</Output>