LARTC - Jul 2005 - izbalancing - a GNU/Linux Firewall/Router Bash Script feauturing Incoming/Outgoing MultiHomed/LoadBalanced Subsystem Management

Hello,

i wrote a simple but useful (i hope) bash script featuring a easly and
fastly configuration method for implementing a Linux Gateway feauturing
Incoming/Outgoing MultiHomed/LoadBalanced Subsystem Management.

I want share this little script.

you can download a copy from the following address:

http://www.initzero.it/products/opensource/izbalancing/download/izbalancing

just save it in your hd and open it with a text editor (vi, emacs,
gedit...) to configure the minimal variables.
the file it self contains istructions... just read.

don''t forget to ''chmod 750 izbalancing'' :-)

Follow the readme contained in the script file:

Best Regards

##############################################################################################
# What is this?
# ============# This bash script allow you to easly and fastly configure a
complex Load Balancing Multi Homed Internet Gateway
# for inbound and outbound traffic

# Key Features:
# ============# - Multiple Balanced Default Gateway Configuration
# - Load Balanced outgoing connections from LAN to INTERNET connections
# - Management of multiple incoming connection from many INTERNET ISP lines to
DMZ/LAN Servers
# - SystemV compliant script... you can run easly at boot up (like Red Hat,
Fedora, SuSE, Mandrake, etc...)
# - Automatically discover your local IP addresses... you can change your IP
without reconfigure this script, just restart
# - Start and Stop Cleanly your MultiHomed Configuration with simple command
(izbalancing start|stop|restart)
# - Adding new Internet Connections is very easy and fast
# - You only must know the TABLE ID to assign to the new line, Ethernet Name of
your NIC, and the Router IP Address

# Requirements:
# ============# - GNU/Linux Firewall running Kernel >=2.6.10 (with iptables
module CONNMARK available)
# - Bash Shell >= 2.0
# - Standard GNU/Linux coreutils utilities (cat, echo, grep, if, etc...)
# - GNU Version of awk and sed utilities
# - GNU/Linux Netfilter user space utilities (iptables >= 1.2.11)
# - iproute2 utilities
# - Two or more Internet connections (also from different ISPs and IP classes)
# - An ethernet card for each ISP Router

# Tested On:
# =========# - GNU/Linux Fedora Core 3 with 2 Internet Connections
# - GNU/Linux Fedora Core 4 with 2 Internet Connections

# Script Usage:
# ============# 1) Configure or add the following variables:
#    TABLEn = Table number of internet connection ''n''
#       IFn = The Ethernet Interface name of internet connection
''n''
#       GWn = The Router IP Address of Internet connection ''n''
# 2) Add a line for any internet connection in the izbalancing function
# 3) Modify the command "ip route add default equalize nexthop via
..." adding all ISP''s Routers IP
# 4) Comment out the iptables rules
# 5) Save this file and execute it a boot time (for Red Hat systems you can copy
this script in /etc/rc.d/init.d/ directory
#    and launch ''chkconfig --add izbalancing'')
 
# That''s all...

-- 
Ugo Viti
Linux Red Hat Certified Engineer

InitZero S.r.l.
Via P. Calamandrei 24, 52100 Arezzo
Tel. +39 0575 1822155 - Fax. +39 0575 1822156
WWW: http://www.initzero.it
E-Mail: info@initzero.it