Install and Configure GNS3

First, You should install gns3:

sudo emerge --autounmask-write gns3
sudo dispatch-conf
sudo emerge gns3

Then you need to prepare for ios images, You can download them from:

ftp://ftp.unikon-ua.net/pub/Cisco/IOS/
http://115.com/file/clsclmjb

Then you should configure them:

Edit>IOS Images and Hypervisors

And calculate ‘Idle PC’。

You may want to get rid of warning of baseconfig.txt, refer to:

http://forum.gns3.net/post12717.html

If you are using KDE, you may use konsole’s preconfigured terminal commands.

Edit>Preferences>General>Terminal Settings

You need to install and configure virtualbox at Edit>Preferences>VirtualBox:

• modify Path to vboxwrapper to:

  /usr/libexec/gns3/vboxwrapper.py
  

• emerge virtualbox with sdk and python USE flags

• install vboxapi:

  cd /usr/lib/virtualbox/sdk/installer/
  export VBOX_INSTALL_PATH=/usr/lib/virtualbox/
  python vboxapisetup.py install
  

• install xdotool(It’s quite an interesting tool!) sudo emerge xdotool
• add virtual system: Edit>Preferences>VirtualBox>VirtualBox Guest

You need to install qemu at Edit>Preferences>Qemu:

• modify Path to qemu:

  qemu-system-x86_64
  

• modify path to qemuwrapper to:

  /usr/libexec/gns3/qemuwrapper.py
  

• kernel should support kvm-intel:

   ⮀ ~ ⮀ lsmod|grep kvm
  kvm_intel             117933  0 
  kvm                   225670  1 kvm_intel
  

• and add you user to:

  gpasswd -a username kvm

• add virtual system, which can be vdi

• If you want to use PIX firewall, download pemu from Sourceforge and cp them to the directory which has qemuwrapper.py. You can reffer to: http://www.gns3.net/documentation/gns3/pix-firewall-emulation/

• if you re-compile kernel, don’t forget to re-compile kernel modules for virtualbox and modprobe them

More configuration

More configuration and downloads(I tried and failed, do not know what is actually is and how to use it):

• 分享–实现用GNS3模拟 PC，PIX，Juniper，ASA，IPS的应用 (中文)

A Simple Test

• Calc idle PC, very important!!

configure the router with the help of OSPF configure(中文)

A better choice to learn without these configuration, try GNS3 WorkBench