Parsing log file with logs of different patterns Logstash - logstash

I am new to logstash in that matter ELK stack. A log file is having different processes logging data to it. Each process writes logs with different patterns. I want to parse this log file. Each log in this log file is started with below grok pattern,
%{SYSLOGTIMESTAMP:timestamp} %{SYSLOGHOST:logsource} %{SYSLOGPROG}: +
%{SRCFILE:srcfile}:%{NUMBER:linenumber} where SRCFILE is defined as
[a-zA-Z0-9._-]+
Please let me know how can I parse this file so that different type of logs from each process logging in this file can be parsed.

Since you're trying to pass in log files, you might have to use the file input plugin in order to retrieve a file or x number of files from a given path. So a basic input could look something like this:
input {
file {
path => "/your/path/*"
exclude => "*.gz"
start_position => "beginning"
ignore_older => 0
sincedb_path => "/dev/null"
}
}
The above is just a sample for you to reproduce. So once you get the files and start processing them line by line, you could use the grok filter in order to match the keywords from your log file. A sample filter could look something like this:
grok {
patterns_dir => ["/pathto/patterns"]
match => { "message" => "%{SYSLOGTIMESTAMP:timestamp} %{SYSLOGHOST:logsource} %{SYSLOGPROG}: + %{SRCFILE:srcfile}:%{NUMBER:linenumber} where SRCFILE is defined as [a-zA-Z0-9._-]+" }
}
You might have to use different filters if you're having different type of logs printed within a single file OR you could have it in the same line with a , comma separated values. Something like:
grok {
match => { "message" => [
"TYPE1,%{WORD:a1},%{WORD:a2},%{WORD:a3},%{POSINT:a4}",
"TYPE2,%{WORD:b1},%{WORD:b2},%{WORD:b3},%{WORD:b4}",
"TYPE3,%{POSINT:c1},%{WORD:c2},%{POSINT:c3},%{WORD:c4}" ]
}
}
And then maybe you could play around with the message, since you've got all the values you needed right within it. Hope it helps!

Related

logstash or filebeat to create multiple output files from tomcat log

I need to parse a tomcat log file and output it into several output files.
Each file is the result of a certain filter that will pick certain entries in the tomcat file that match a series of regexes or other transformation rule.
Currently I am doing this using a python script but it is not very flexible.
Is there a configurable tool for doing this?
I have looked into filebeat and logstash [none of which I am very familiar with] but it is not clear if it is possible to configure them to map a single input file into multiple output files each with a different filter/grok set of expressions.
Is it possible to achieve this with filebeat/logstash?
If all logs files are on the same servers you dont need Filebeat. Logstash can do the work.
Here an example of what your config logstash can look like.
In input you have you tomcat log file and you have multi output (json) depend of loglevel once logs have been parsed.
The grok is also an example you must define your own grok pattern depend on your log format.
input {
file {
path => "/var/log/tomcat.log"
}
}
filter {
grok {
match => { "message" => "%{TIMESTAMP_ISO8601:timestamp} %{LOGLEVEL:loglevel} - %{POSTFIX_SESSIONID:sessionId}: %{GREEDYDATA:messageText}" }
}
}
output {
if [loglevel] == "info" {
file {
codec => "json"
path => "/var/log/tomcat_info_parsed.log"
}
}
if [loglevel] == "warning" {
file {
codec => "json"
path => "/var/log/tomcat_warning_parsed.log"
}
}
}

Logstash not producing output or inserting to elastic search

When i execute the configuration file using the command bin\logstash -f the configfile.conf. There is not display on the console just the logs by logstash.
Here is the configuation file:
input
{
file
{
path => "F:\ELK\50_Startups.csv"
start_position => "beginning"
}
}
filter
{
csv
{
separator => ","
columns => ["R&D","Administration","Marketing","State","Profit"]
}
}
output
{
elasticsearch
{
hosts => ["localhost:9200"]
index => ["Startups"]
}
stdout{}
}
do the input file (50_Startups.csv) has fresh data written to? if not, it might be that logstash already stored the read offset as the last line, and it would not re-read it on future runs, unless you delete the sincedb_path offset files, of just add the following config:
sincedb_path => "/dev/null"
That would force logstash to re-parse the file.
see more info on files offsets here:https://www.elastic.co/guide/en/logstash/current/plugins-inputs-file.html#_tracking_of_current_position_in_watched_files
from it:
By default, the sincedb file is placed in the data directory of Logstash with a filename based on the filename patterns being watched

logstash simple file input/output

I have trouble getting logstash to work. The Basic logstash Example works. But then I struggle with the Advanced Pipeline Example. Perhaps it could be as well a problem with elasticsearch.
Now I just want to check if a simple example work:
input: read textfile-a
output: generate new textfile-b with input of the textfile-a
But I am struggling with that. My config is the following:
# foo.conf
input {
file {
path => "C:/logstash-2.3.1/logstash-tutorial-dataset"
start_position => "beginning"
}
}
output {
stdout {}
file {
#message_format => "%{foo},%{bar},%{fii},%{bor},%{bing}"
#codec => { line { format => "custom format: %{message}"}}
path => "C:/output.txt"
}
}
When I run logstash, I get the following response and nothings happens.
bin/logstash -f foo.conf -v --debug --verbose
io/console not supported; tty will not be manipulated
{:timestamp=>"2016-04-22T13:41:15.514000+0200", :message=>"starting agent", :level=>:info}
{:timestamp=>"2016-04-22T13:41:15.518000+0200", :message=>"starting pipeline", :id=>"main", :level=>:info}
{:timestamp=>"2016-04-22T13:41:16.035000+0200", :message=>"Registering file input", :path=>["C:/logstash-2.3.1/logstash-tutorial-dataset"], :level=>:info}
{:timestamp=>"2016-04-22T13:41:16.039000+0200", :message=>"No sincedb_path set, generating one based on the file path", :sincedb_path=>"c:/Users/foobar/.sincedb_802dc9c88c8fad631bf3d3a5c96435e4", :path=>["C:/logstash-2.3.1/logstash-tutorial-dataset"], :level=>:info}
{:timestamp=>"2016-04-22T13:41:16.103000+0200", :message=>"Starting pipeline", :id=>"main", :pipeline_workers=>4, :batch_size=>125, :batch_delay=>5, :max_inflight=>500, :level=>:info}
{:timestamp=>"2016-04-22T13:41:16.106000+0200", :message=>"Pipeline main started"}
how do I get the simple example working?
ignore_older => 0 did the trick, see documentaion: ignore_older.
The working configuration is the following:
# foo.conf
input {
file {
path => "C:/logstash-2.3.1/logstash-tutorial-dataset"
start_position => "beginning"
ignore_older => 0
}
}
output {
stdout {}
file {
path => "C:/output.txt"
}
}
Now the .sincedb* file contains as well content.
Logstash remembers which files it has processed, and how much of them it has processed. In normal operations, this allows it to restart in case of failure and not reprocess logs.
In your case, I imagine that your log file has been processed once already, so logstash is ignoring it. The "start_position" parameter you've provided is documented to only apply to new files.
You would either need to reset your registry (perhaps files like /var/lib/logstash/.sincedb*), or set the "sincedb_path" parameter in your file{} into to /dev/null so that it doesn't maintain the history while you're testing.

Seems Logstash doesn't process the last event/line until the next event is written

I am new to logstash and during my hands on I could see that logstash do not process the last line of the log file.
My log file is simple 10 lines and I have configured filters to process one/two fields and output the json result to a new file.
So when logstash is running I open the monitored file and add one line to the end of file and save it. Nothing happens. Now I add one more line and the previous event shows up in the output file, and similarly for the next events.
How to resolve this behavior ? Is something wrong with my usecase/config ?
# The # character at the beginning of a line indicates a comment. Use
# comments to describe your configuration.
input {
file {
path => "C:\testing_temp\logstash-test01.log"
start_position => beginning
}
}
# The filter part of this file is commented out to indicate that it is
# optional.
filter {
grok {
match => { "message" => "%{IP:clientip} pssc=%{NUMBER:response} cqhm=%{WORD:HTTPRequest}"}
}
geoip {
source => "clientip"
}
}
output {
file {
path => "C:\testing_temp\output.txt"
}
}
please make sure to add a a newline at the end of your line when manually inserting. Logstash will pick up your changes as soon as it detects that the line is "finished".
Your usecase is ok. If you add:
stdout { codec => rubydebug }
To your output section you will see the events immediately in your console (nice for debugging/testing).

Extracting fields from input file path logstash?

I want to read my log files from various directories, like: Server1, Server2...
Server1 has subdirectories as cron, auth...inside these subdirectories is the log file respectively.
So I am contemplating of reading files like this:
input{
file{
#path/to/folders/server1/cronLog/cron_log
path => "path/to/folders/**/*_log"
}
}
However, I am having difficulty in filtering them i.e to know that for which server (Server1) and logtype (cron), I must apply the grok pattern:
Eg: I thought of doing something like this
if [path] =~ "auth"{
grok{
match => ["message", ***patteren****]
}
}else if [path] =~ "cron"{
grok{
match => ["message", ***pattern***]
}
Above cron is for log file (not cronLog directory).
But like this I also want to filter on server name as every server will have cron, auth,etc logs.
How to filter on both?
Is there a way to grab directory names from path in input ?? Like from here
path => "path/to/folders/**/*_log"
How should I proceed? Any help is appreciated?
its very straight forward, and almost exactly like in my other answer... you use the grok on the path to extract the pieces out that you care about and then you can do whatever you want from there
filter {
grok { "path", "path/to/here/(?<server>[^/]+)/(?<logtype>[^/]+)/(?<logname>.*) }
if [server] == "blah" && [logtype] =~ "cron" {
grok { "message", "** pattern **" }
}
}

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