Getting a console on a router

  • Drag and drop a router onto the working space
  • Click on the play button (triangle)
  • Right mouse click on the router -> console
  • If the setup configruation after the first boot fails or freezes -> Dont panic!
  • Delete the router
  • Create a new one
  • Skip first setup and configure it manually

Configure a Cisco Switch

  • switches must be simulated as a router
  • cisco catalyst switches must use platform c3600 or c3700
  • right click on the router -> configure
  • in the slots tab choose NM-16ESW on slot1
  • you only be able to start some catalyst images in gns3 (see
  • c3640-is-mz.123-14.T6.bin is known to be working as well

Configuring hosts

  • Install a Qemu Linux (or whatever OS you desire) Image (or download one from
  • Goto Edit -> Preferences -> Qemu
  • Check that the path of is right
  • Try to execute
  • If there are errors try to fix them
  • On Arch linux you have to change python into python2 on the first line of the script
  • Insert the path to your Qemu image in “Path to quemu-img”
  • To test or manipulate Qemu images you can either mount it into your filesystem or start it with Qemu
  • mount -n -o loop <path-to-qemu-image> /mnt
  • qemu <path-to-qemu-image>
  • for more information see

Use your own Linux system as host os

  • Download the ISO of your Linux distro as distro.iso
  • Create a qemu harddisk
  • qemu-img create linux.img 2G
  • qemu -hda linux.img -cdrom distro.iso -boot -d -m 512