Share your story
The central voice for Linux and Open Source security news
Home News Topics Advisories HOWTOs Features Newsletters About Register

Sign up!
EnGarde Community
What is the most important Linux security technology?
Linux Events
Linux User Groups
Link to Us
Security Center
Book Reviews
Security Dictionary
Security Tips
White Papers
Featured Blogs
All About Linux
DanWalsh LiveJournal
Latest Newsletters
Linux Security Week: March 30th, 2015
Linux Advisory Watch: March 27th, 2015
LinuxSecurity Newsletters
Choose Lists:
About our Newsletters
RSS Feeds
Get the LinuxSecurity news you want faster with RSS
Powered By

Client: Configure Networking

5.14. Client: Configure Networking

Now we should setup the networking on our client box. Let's assume that we've configured the external network and that it works. Now we will configure the internal interface of the client to service our intranet.

5.14.1. Interface

We need to first bring up the internal network interface. To do this, add the following to your /etc/rc.d/rc.inet1 (or equivalent) file:

For 2.0 Kernels:

/sbin/ifconfig eth1 broadcast netmask
/sbin/route add -net netmask dev eth1

For 2.2 Kernels:

/sbin/ifconfig eth1 broadcast netmask

5.14.2. Filter rules

To set up the remote office, we will want to set up our filter rules that allow traffic to go both directions through the tunnel. Add the following lines to your /etc/rc.d/rc.inet1 (or equivalent) file:

For 2.0 kernels:

/sbin/ipfwadm -F -f
/sbin/ipfwadm -F -p deny
/sbin/ipfwadm -F -a accept -b -S -D

For 2.2 kernels:

/sbin/ipchains -F forward
/sbin/ipchains -P forward DENY
/sbin/ipchains -A forward -j ACCEPT -b -s -d

You may have noticed that these lines look like what we have on the server. That's because they are the same. These rules just say where traffic is allowed to go between these two networks.

5.14.3. Routing

The only extra routes that are needed are created by the script that bring the tunnel up.



Latest Features
Peter Smith Releases Linux Network Security Online
Securing a Linux Web Server
Password guessing with Medusa 2.0
Password guessing as an attack vector
Squid and Digest Authentication
Squid and Basic Authentication
Demystifying the Chinese Hacking Industry: Earning 6 Million a Night
Free Online security course (LearnSIA) - A Call for Help
What You Need to Know About Linux Rootkits
Review: A Practical Guide to Fedora and Red Hat Enterprise Linux - Fifth Edition
Yesterday's Edition
Feds Charged With Stealing Money During Silk Road Investigation
EFF questions US government's software flaw disclosure policy
Hotel Router Vulnerability A Reminder Of Untrusted WiFi Risks
Partner Sponsor

Community | HOWTOs | Blogs | Features | Book Reviews | Networking
 Security Projects |  Latest News |  Newsletters |  SELinux |  Privacy |  Home
 Hardening |   About Us |   Advertise |   Legal Notice |   RSS |   Guardian Digital
(c)Copyright 2015 Guardian Digital, Inc. All rights reserved.