#!/bin/sh

: << =cut

=head1 NAME

lxc_net - Munin plugin to graph traffic of active LXC containers.

=head1 APPLICABLE SYSTEMS

LXC container with "lxc.network.type=veth" and "lxc.network.veth.pair" settings.

=head1 CONFIGURATION

env.lxcpath - Set the path where LXC containers are stored, default: /var/lib/lxc
env.exclude - Removing containers from graphs, default: empty

  [lxc_net]
    env.lxcpath /var/lib/lxc
    env.exclude container1 container2

=head1 INTERPRETATION

This plugin reads a "lxc.network.veth.pair" setting from "config" file of each container,
because lxc-start command creates a random named veth device without the setting, which
changes at each run.

=head1 AUTHOR

mitty   mitty@mitty.jp
(many changes schaefer@alphanet.ch)

=head1 LICENSE

2-clause BSD License
or GPLv3 license, at your option

=head1 MAGIC MARKERS

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

=cut

. $MUNIN_LIBDIR/plugins/plugin.sh

. $MUNIN_LIBDIR/plugins/lxc-lib

active_guests=$(active_guests $exclude)

if [ "$1" = "autoconf" ]; then
   if [ ! -r /proc/net/dev ]; then
      echo "no (/proc/net/dev cannot be read)"
      exit 0
   fi
   if [ ! -e "$lxcpath" ]; then
      echo "no ($lxcdir is not present)"
      exit 0
   fi
    
   echo yes
   exit 0
fi

if [ "$1" = "config" ]; then
   cat <<EOF
graph_title Network traffic
graph_args --base 1000
graph_vlabel bits in (-) / out (+) per ${graph_period}
graph_category lxc
graph_info This graph shows the traffic of active LXC containers.
EOF
    
   for n in $active_guests
   do
      g=$(lxc_clean_fieldname $n)
      device=$(lxc_netdev $n)
      if [ "$device" = "unknown" ]; then
         continue
      fi
      bps="U"
      if [ -r /sys/class/net/$device/speed ]; then
         bps=$(($(cat /sys/class/net/$device/speed) * 1000 * 1000))
      fi
      cat <<EOF
net_${g}_down.label $n
net_${g}_down.type DERIVE
net_${g}_down.graph no
net_${g}_down.cdef net_${g}_down,8,*
net_${g}_down.min 0
net_${g}_down.max $bps
net_${g}_up.label $n
net_${g}_up.type DERIVE
net_${g}_up.negative net_${g}_down
net_${g}_up.cdef net_${g}_up,8,*
net_${g}_up.min 0
net_${g}_up.max $bps
EOF
   done
   exit 0
fi

for n in $active_guests
do
   g=$(lxc_clean_fieldname $n)
   device=$(lxc_netdev $n)
   if [ "$device" = "unknown" ]; then
      continue
   fi

   cat <<EOF
net_${g}_up.value $(egrep "^ *${device}:" /proc/net/dev | awk '{print $10;}')
net_${g}_down.value $(egrep "^ *${device}:" /proc/net/dev | awk '{print $2;}')
EOF
done