Selfhosted

39937 readers

345 users here now

A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don't control.

Rules:

Be civil: we're here to support and learn from one another. Insults won't be tolerated. Flame wars are frowned upon.
No spam posting.
Posts have to be centered around self-hosting. There are other communities for discussing hardware or home computing. If it's not obvious why your post topic revolves around selfhosting, please include details to make it clear.
Don't duplicate the full text of your blog or github here. Just post the link for folks to click.
Submission headline should match the article title (don’t cherry-pick information from the title to fit your agenda).
No trolling.

Resources:

selfh.st Newsletter and index of selfhosted software and apps
awesome-selfhosted software
awesome-sysadmin resources
Self-Hosted Podcast from Jupiter Broadcasting

Any issues on the community? Report it using the report flag.

Questions? DM the mods!

founded 1 year ago

MODERATORS

[email protected]

Parsing RFC3164 logs for Grafana (lemmy.sdf.org)

submitted 1 year ago by [email protected] to c/[email protected]

9 comments fedilink hide all child comments

Hey everyone ! I finally decided to monitor my applications more closely with Grafana. However I'm having issues building dashboards their logs.

Their logs are currently sent over syslog (in RFC3164 format) into telegraf. But it simply puts the whole message into the message field, so I can't use specific fields (eg. URL for httpd, source IP for DNS requests, username for SSH, …) to build graphs.

I've read about grok patterns, but I have no idea how to use them.

Would someone have any pointer on how I could make sense out of these logs for later use ?

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 1 points 1 year ago

I found how to parse and tokenize logs withing telegraf. One must use grok patterns to parse the logs. Here is the config sample I use:

# bind locally to ingest syslog messages
[[inputs.syslog]]
   server = "udp://<ipaddress>:6514"
   syslog_standard = "RFC3164"

[[processors.parser]]
  parse_fields = ["message"]
  merge = "override"
  data_format = "grok"
  grok_patterns = ["%{HTTPD}", "%{GEMINI}"] # this must reference the name from grok_custom_patterns
  # format; PATTERN_NAME GROK_PATTERN…
  grok_custom_patterns = '''
HTTPD ^%{HOSTNAME:httphost} %{COMBINED_LOG_FORMAT} (?:%{IPORHOST:proxyip}|-) (?:%{NUMBER:proxyprot}|-)$
GEMINI ^(?:\"(?:gemini\:\/\/%{HOSTNAME:gmihost}(:%{NUMBER:gmiport})?%{NOTSPACE:request}|%{DATA:raw_request})\" %{NUMBER:response} %{NUMBER:bytes}|%{DATA})$
  '''

# send parsed logs to influxdb
[[outputs.influxdb]]
  urls = ["http://localhost:8086"]
  database = "telegraf"

Telegraf supports logstash core patterns, as well as its own custom patterns (like %{COMBINED_LOG_FORMAT}).

You can then query your influxdb using the fields extracted from these patterns:

> USE telegraf
> SELECT xff,httphost,request FROM syslog WHERE appname = 'httpd' AND verb = 'GET' ORDER BY time DESC