April 2004
Intermediate to advanced
320 pages
9h 10m
English
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Tunnel with VTun and SSH
Connect two networks using VTun and a single SSH connection.
VTun is a user-space tunnel server,
allowing entire networks to be tunneled to each other using the
tun universal tunnel kernel driver.
An encrypted tunnel such as
VTun allows roaming wireless clients to secure
all of their IP traffic using strong encryption. It currently runs
under Linux, BSD, and Mac OS X.
The examples in this hack assume that you are using Linux.
The procedure described next will allow a host with a private IP address (10.42.4.6) to bring up a new tunnel interface with a real, live, routed IP address (208.201.239.33) that works as expected, as if the private network weren’t even there. Do this by bringing up the tunnel, dropping the default route, and then adding a new default route via the other end of the tunnel.
To begin with, here is the (pretunneled) network configuration:
root@client:~# ifconfig eth2 eth2 Link encap:Ethernet HWaddr 00:02:2D:2A:27:EA inet addr:10.42.3.2 Bcast:10.42.3.63 Mask:255.255.255.192 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:662 errors:0 dropped:0 overruns:0 frame:0 TX packets:733 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:105616 (103.1 Kb) TX bytes:74259 (72.5 Kb) Interrupt:3 Base address:0x100 root@client:~# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.42.3.0 * 255.255.255.192 U 0 0 0 eth2 loopback * 255.0.0.0 U 0 0 0 lo default 10.42.3.1 0.0.0.0 UG 0 ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.