So, perhaps you are too far from your local exchange to get a decent DSL speed, or you have an urgent large download and want to use a secondary internet connection to boost your speed. This article will allow you to combine 2 connections together. No ISP support is required. Connections could be all DSL, 2.4Ghz wireless, or HSDPA or any combination of, indeed any type of internet connection (latency permitting).
There are a number of expensive products on the market which do this. I want to bring this into the realms of the sys admin/computer hobbyist, after all this is the information age.
In this example I am using 1 DSL connection, with 1 HSDPA connection, but assuming you know enough to be able to implement this you should be able to change interface names or implement for more than 2 connections if you want.
You will need:-
- A computer of some sort with Ubuntu loaded on it (only for the purposes of this article, could easily be any other distro if you are prepared to adapt it).
- A dedicated server of some sort on the internet with Ubuntu (again another distro if you want to adapt, I can recommend a Kimsufi 2G for €14.99 per month ex VAT, can’t get better value than that)
- 2 internet connections, obviously.
We will be using a VPN and multi-link PPP to bundle the 2 connections together. The traffic will go through the dedicated server onto the net as follows:-
LAN <-> Masquerading/SNAT <-> VTUN <-> multi-link PPP <-> VTUN <-> SNAT <-> Internet.
First of all we have to setup policy routing so that the 2 VPN tunnels go through the correct interfaces, otherwise this is all a waste of time. We are going to setup 2 routing tables 1 for each connection.
/etc/iproute2/rt_tables
# # reserved values # 255 local 254 main 253 default 0 unspec # # local # #1 inr.ruhep # Routing table for DSL connection 101 dsl-connection # Routing table for HSDPA connection 102 hsdpa-connection
We then have to remove any default route/gateway from the network setup and add the policy routing rule which will tell the computer to route traffic through the correct interface.
/etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
# The loopback network interface
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address 192.168.1.254
netmask 255.255.255.0
# Rule to route everything originating from the DSL interface through the DSL gateway
post-up ip rule add from 192.168.1.254 lookup dsl-connection
# Gateway for DSL connection
post-up ip route add default via 192.168.1.252 table dsl-connection
The following file is the setup for the HSDPA connection (in my case to Three), adjust accordingly for your own provider. Refer to http://johnlewis.ie/mobile-broadband-from-the-command-line-in-ubuntu/ for the chat script and pap-secrets.
/etc/ppp/peers/provider
user "user" connect "/usr/sbin/chat -v -f /etc/chatscripts/pap -T *99#" # Serial device to which the modem is connected. /dev/ttyUSB0 # Do not use this connection as the default route. nodefaultroute # Makes pppd "dial again" when the connection is lost. persist # no compression - ppp is used only until the modem novj novjccomp nopcomp nodeflate noccp
The following file sets up the correct routing for the HSDPA connection once it is up.
/etc/ppp/ip-up.d/bond-route
#!/bin/sh # Rule to route everything originating from the HSDPA interface through the HSDPA gateway # Notice we use a network here as opposed to a singular IP address or interface name # This is because the IP address is dynamic but always in the 10.0.0.0 range # And also because routing rules by interface name don't appear to work at the moment ip rule add from 10.0.0.0/8 lookup hsdpa-connection # Gateway for HSDPA connection # Similarly using the fake gateway assigned by pppd in the absence of provider supplied # Succesfully routes out of the correct interface, again as interface name doesn't work ip route add default via 10.64.64.64 table hsdpa-connection
Install Vtun and edit config as necessary.
/etc/vtund.conf
options {
port 5000; # Listen on this port.
# Path to various programs
ppp /usr/sbin/pppd;
ifconfig /sbin/ifconfig;
route /sbin/route;
firewall /sbin/tables;
ip /sbin/ip;
}
# Default session options
default {
# type tun; #tun, ether, tty(default), pipe
# proto tcp; #udp, tcp
compress no; # no, yes, zlib, lzo
encrypt no; #yes, no
stat yes; #yes, no: check /var/log/vtund/SessionName_X
speed 0; # By default maximum speed, NO shaping
}
# PPP tunnel example.
DSL-PPP-Tunnel {
passwd yourpassword; # Password
type tty; # PPP tunnel.
proto tcp; # UDP/TCP protocol
# compress lzo:9; # LZO compression level 9
encrypt no; # Encryption
# keepalive yes; # Keep connection alive
# persist yes;
srcaddr {
iface eth0; # Use first up-/ downstream-device
};
up {
# Connection is Up
ppp "file /etc/ppp/options.vtund";
};
down {
# Connection is down
};
}
HSDPA-PPP-Tunnel {
passwd yourpassword; # Password
type tty; # PPP tunnel.
proto tcp; # UDP/TCP protocol
# compress lzo:9; # LZO compression level 9
encrypt no; # Encryption
# keepalive yes; # Keep connection alive
# persist yes;
srcaddr {
iface ppp0; # Use first up-/ downstream-device
};
up {
# Connection is Up
ppp "file /etc/ppp/options.vtund";
};
down {
# Connection is down
};
}
Here we set the options for PPP.
/etc/ppp/options.vtund
noauth lock debug dump #logfd 1 logfile /var/log/vtund.log passive updetach #To Enable PPP compression Comment the following line. --START-- noccp novj novjccomp nopcomp noaccomp #To Enable PPP compression Comment the following line. --END-- # Set the tunnel endpoint as the default gateway for the entire machine defaultroute # Enable multlink so this connection can be used in a bundle mp
/etc/default/vtun
# Defaults for vtun initscript # sourced by /etc/init.d/vtun # Created by the maintainer scripts # # This is a POSIX shell fragment # # Should the standalone server be started? # RUN_SERVER=no # SERVER_ARGS="-P 5000" # Client sessions to start. Up to ten instances can be configured. # # Session name # CLIENT0_NAME=viper # # Destination host # CLIENT0_HOST=vtun-server.somewhere.com.au # # Optional parameters # CLIENT0_ARGS= # # CLIENT1_NAME= # CLIENT1_HOST= # CLIENT1_ARGS= CLIENT0_NAME=DSL-PPP-Tunnel # Real IP address of dedicated server running vtun, adjust accordingly CLIENT0_HOST=188.165.0.43 CLIENT1_NAME=HSDPA-PPP-Tunnel # Real IP address of dedicated server running vtun, adjust accordingly CLIENT1_HOST=188.165.0.43
/etc/sysctl.conf
net.ipv4.ip_forward=1
/etc/rules-save
# Generated by iptables-save v1.4.10 on Thu Aug 11 20:02:56 2011 *filter :INPUT ACCEPT [308:33472] :FORWARD ACCEPT [150:16924] :OUTPUT ACCEPT [259:26848] COMMIT # Completed on Thu Aug 11 20:02:56 2011 # Generated by iptables-save v1.4.10 on Thu Aug 11 20:02:56 2011 *nat :PREROUTING ACCEPT [87:6487] :INPUT ACCEPT [2:412] :OUTPUT ACCEPT [37:2646] :POSTROUTING ACCEPT [37:2646] # Rule to Masquerade/NAT the local network change accordingly -A POSTROUTING -s 192.168.1.0/24 -o ppp1 -j MASQUERADE COMMIT # Completed on Thu Aug 11 20:02:56 2011
/etc/rc.local
#!/bin/sh -e # # rc.local # # This script is executed at the end of each multiuser runlevel. # Make sure that the script will "exit 0" on success or any other # value on error. # # In order to enable or disable this script just change the execution # bits. # # By default this script does nothing. # Start HSDPA connection pon # Load ftp connection tracking module modprobe nf_conntrack_ftp # Restore previous iptables config iptables-restore /etc/rules-save # Restart the local DNS caching server if you have one service dnsmasq restart exit 0
At the server end we have to setup Vtun, PPP and source NAT.
/etc/vtund.conf
options {
port 5000; # Listen on this port.
# Path to various programs
ppp /usr/sbin/pppd;
ifconfig /sbin/ifconfig;
route /sbin/route;
firewall /sbin/tables;
ip /sbin/ip;
}
# Default session options
default {
# type tun; #tun, ether, tty(default), pipe
# proto tcp; #udp, tcp
compress no; # no, yes, zlib, lzo
encrypt yes; #yes, no
stat yes; #yes, no: check /var/log/vtund/SessionName_X
speed 0; # By default maximum speed, NO shaping
}
DSL-PPP-Tunnel {
passwd yourpassword; # Password to authenticate the vtund client
type tty; # PPP tunnel.
proto tcp; # Use UDP or TCP protocol
# compress lzo:9; # LZO compression level 9
encrypt no; # Encryption
keepalive yes; # Keep connection alive
up {
# Connection is Up
ppp "file /etc/ppp/options.vtund";
};
down {
# Connection is down
};
}
HSDPA-PPP-Tunnel {
passwd yourpassword; # Password to authenticate the vtund client
type tty; # PPP tunnel.
proto tcp; # Use UDP or TCP protocol
# compress lzo:9; # LZO compression level 9
encrypt no; # Encryption
keepalive yes; # Keep connection alive
up {
# Connection is Up
ppp "file /etc/ppp/options.vtund";
};
down {
# Connection is down
};
}
/etc/ppp/options.vtund
noauth lock #debug #dump #logfd 2 #To Enable PPP compression Comment the following line. --START-- noccp novj novjccomp nopcomp noaccomp #To Enable PPP compression Comment the following line. --END-- # Enable multilink bundling mp #Set local and remote IP addresses for the PPP connection 192.168.10.1:192.168.10.2
/etc/default/vtun
# Defaults for vtun initscript # sourced by /etc/init.d/vtun # Created by the maintainer scripts # # This is a POSIX shell fragment # # Should the standalone server be started? RUN_SERVER=yes # SERVER_ARGS="-P 5000" # Client sessions to start. Up to ten instances can be configured. # # Session name # CLIENT0_NAME=viper # # Destination host # CLIENT0_HOST=vtun-server.somewhere.com.au # # Optional parameters # CLIENT0_ARGS= # # CLIENT1_NAME= # CLIENT1_HOST= # CLIENT1_ARGS=
/etc/rc.local
#!/bin/sh -e # # rc.local # # This script is executed at the end of each multiuser runlevel. # Make sure that the script will "exit 0" on success or any other # value on error. # # In order to enable or disable this script just change the execution # bits. # # By default this script does nothing. iptables -t nat -A POSTROUTING -s 192.168.10.0/24 -o eth0 -j SNAT --to 188.165.0.43 exit 0
http://www.opennet.ru/soft/vpn_table/vtund-ppp1.html
http://www.dslreports.com/forum/r20456553-MLPPP-Guide-on-Linux