NXLog Reading mssql errorlog lines, are send incomplete.

#1 Felix Roberto Read Rivero (Last updated )

Good Day, 

I installed nxlog to ready to ready my mssql errorlog file, and send it to graylog server, but for some reason the message is not coming complete,

here is my conf

I omitted the rest because it just the default configuration file 

<Extension charconv> 
   Module      xm_charconv
   AutodetectCharsets iso8859-2, utf-8, utf-16, utf-32,UCS-2LE

<Extension gelf>
   Module xm_gelf

<Input mssql_errorlog>
   Module      im_file
   File        "D:\Program Files\Microsoft SQL Server\MSSQL14.MSSQLSERVER\MSSQL\Log\ERRORLOG"

<Output graylog_udp>
   Module om_udp
   Port 12202
   OutputType    GELF_UDP

<Route graylog_route_mssql_errorlog>
   Path mssql_errorlog => graylog_udp_204

This is the line in my ERRORLOG

2023-05-26 10:00:13.50 Logon       Login failed for user 'localnet\sqljobs'. Reason: Could not find a login matching the name provided. [CLIENT: <local machine>]

And this is the message i get in graylog


 "gl2_accounted_message_size": 242,
 "SourceModuleType": "im_file",
 "level": 6,
 "gl2_remote_ip": "",
 "gl2_remote_port": 60459,
 "streams": [
 "gl2_message_id": "01H1C5R90HW9F49TPRA9XXQ93E",
 "source": "sql-dev",
 "message": "2\u00000\u00002\u00003\u0000-\u00000\u00005\u0000-\u00002\u00006\u0000 \u00001\u00000\u0000:\u00000\u00000\u0000:\u00001\u00003\u0000.\u00005\u00000\u0000 \u0000L\u0000o\u0000g\u0000o\u0000n",
 "gl2_source_input": "646f94d504777573d7d0c945",
 "EventReceivedTime": "2023-05-26 10:00:13",
 "SourceModuleName": "mssql_errorlog",
 "gl2_source_node": "332a47fa-bf25-4d8f-8e25-ce6dedb6a67a",
 "_id": "a2c1f101-fbcd-11ed-87a7-00505687667c",
 "timestamp": "2023-05-26T14:00:13.000Z"



And this is the result parsed by graylog

message : 2023-05-26 10:00:13.50 Logon

Any one has any idea what could be wrong? 

#2 konstantinos

Hi Felix,

Before sending the events towards Graylog in GELF format, the events need to be parsed into fields. This logic is missing from your Input block, hence the transformation to GELF will not succeed. 

Also for ERRORLOG, it is advisable to normalize the encoding to UTF-8.

Please have a look at the second example at: https://docs.nxlog.co/userguide/integrate/mssql-server.html#microsoft-sql-server-error-log