Munin Plugin - nginx error_log

nginx_error_log

#!/bin/bash
: <<=cut

=head1 NAME

nginx error log - Munin plugin to monitor nginx error_log rates (debug, info, notice, warn, error, crit, alert, emerg).

=head1 APPLICABLE SYSTEMS

Any Linux host, running nginx, with bash version > 4.0

=head1 CONFIGURATION

This shows the default configuration of this plugin.  You can override
the log file path and the logpattern.

  [nginx_error_log]
        env.logpath    /var/log/nginx
        env.logpattern *error.log

=head1 USAGE

Link this plugin to /etc/munin/plugins/ and restart the munin-node.

This plugin also can be used like wildcard-plugin for monitoring particular virtual host log.
E.g.
    ln -s /usr/share/munin/plugins/nginx_error_log /etc/munin/plugins/nginx_error_log_mydomaincom
will parse the log file /var/log/nginx/mydomaincom_error.log

You can change 'env.logpattern' using asterisk ('*') to match your logs filenames.

=head1 INTERPRETATION

The plugin shows nginx error_log rates by severity by parsing error logs.

=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=head1 BUGS

None known.

=head1 VERSION

$Id:$

=head1 AUTHOR

[email protected], 2014
Adapted from script by [email protected], 2013
https://github.com/munin-monitoring/contrib/blob/master/plugins/nginx/nginx_error

=head1 LICENSE

GPLv3

=cut

if [ -z $logpath ]; then
  logpath='/var/log/nginx'
fi

if [ -z $logpattern ]; then
  name=`basename $0`
  domain=${name/nginx_error_log/}
  if [[ $domain != '_' && ${#domain} -ne 0 ]]; then
    domain=${domain:1}
    if [ -z $logpattern ]; then
      logpattern='*_error.log'
    fi
    logpattern=${logpattern/\*/$domain}
  else
    logpattern='error.log'
  fi
fi

log="$logpath/$logpattern"

# declaring an array with http status codes, we are interested in
declare -A levels
levels[debug]='Debug'
levels[info]='Info'
levels[notice]='Notice'
levels[warn]='Warning'
levels[error]='Error'
levels[crit]='Critical'
levels[alert]='Alert'
levels[emerg]='Emergency'

do_ () { # Fetch
  for k in ${!levels[@]}; do
    value=`awk -v k="[$k]" '{if ($3 == k) { i += 1 }} END { print i }' $log` # this is much better
    echo "$k.value ${value:-0}"
  done
  exit 0
}

do_config () {
  echo "graph_title nginx error logs per minute - $logpattern"
  echo 'graph_vlabel log messages / ${graph_period}'
  echo "graph_category nginx"
  echo "graph_period minute"
  echo "graph_info This graph shows nginx error log amount per minute"
  for k in ${!levels[@]}; do
    echo "$k.type DERIVE"
    echo "$k.min 0"
    echo "$k.label $k"
  done
  exit 0
}

do_autoconf () {
  echo yes
  exit 0
}

case $1 in
  config|autoconf|'')
  eval do_$1
esac

exit $?