My .i3blocks.conf and /usr/libexec/i3blocks/network

.i3blocks.conf

# ArchieT's i3blocks config file
# state as of 2015-07-18
#
# Please see man i3blocks for a complete reference!
# The man page is also hosted at http://vivien.github.io/i3blocks
#
# List of valid properties:
#
# align
# color
# command
# full_text
# instance
# interval
# label
# min_width
# name
# separator
# separator_block_width
# short_text
# signal
# urgent

# Global properties
separator_block_width=15

[volume]
label=VOL
#label=♪
instance=Master
#instance=PCM
command=/usr/libexec/i3blocks/volume
interval=once
signal=10

[memory]
label=MEM
command=/usr/libexec/i3blocks/memory
separator=false
interval=2

[swap]
label=SWAP
instance=swap
command=/usr/libexec/i3blocks/memory
interval=2

[disk-home]
instance=$HOME
command=/usr/libexec/i3blocks/disk
interval=30

[wireless]
label=W
instance=wlan0
#instance=wlp2s0
command=/usr/libexec/i3blocks/network
color=#00FF00
interval=4

[ethernet]
label=E
instance=eth0
#instance=enp4s1
command=/usr/libexec/i3blocks/network
color=#00FF00
interval=4

[ethernet]
label=U
instance=usb0
command=/usr/libexec/i3blocks/network
color=#00FF00
interval=4

[cpu]
label=CPU
command=/usr/libexec/i3blocks/cpu_usage
interval=1
min_width=CPU: 100.00%
#separator=false

[temp]
label=T
command=sensors acerhdf-virtual-0 | awk '/temp1/ { print $2 }'
interval=1

[load]
command=/usr/libexec/i3blocks/load_average
interval=5

[battery]
#label=BAT
label=⚡
command=/usr/libexec/i3blocks/battery
interval=3

[time]
command=date '+%Y-%m-%d %H:%M:%S'
interval=1

network

#!/bin/sh
# Copyright (C) 2014 Julien Bonjean <julien@bonjean.info>
# modified 2015 by ArchieT <feiler.michal@mensa.org.pl>

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

INTERFACE="${BLOCK_INSTANCE:-eth0}"

state="$(cat /sys/class/net/$INTERFACE/operstate)"

if [ "$state" == "down" ]; then
	echo "down"
	echo "down"
	echo "#FF0000"
	exit 0
fi

speed="$(cat /sys/class/net/$INTERFACE/speed 2> /dev/null)"

ipaddr="$(ip addr show $INTERFACE | perl -n -e'/inet (.+)\// && print $1')"
ipaddr="${ipaddr:-0.0.0.0}"

# full text
echo -n "$ipaddr"
[ -n "$speed" ] && echo " ($speed Mbits/s)" || echo

# short text
echo "$ipaddr"

if [ "$ipaddr" == "0.0.0.0" ]; then
	if [ "$state" == "up" ]; then
		echo "#0069FF"
		exit 0
	fi
	echo "#555555"
fi