Setup for a Macintosh Machine
The GNS3 Network Simulator / Emulator for mac OS
Go to https://gns3.com/ and click on “Free Download”. You will be asked to sign up, so enter the details and continue. Select the installer for your OS, and click on that version.Advanced Option – Dual-booting
Advanced computer users could consider the possibility of dual-booting Ubuntu. As a first step before attempting this, you must make a full backup of all your important files – applications and system files included. You may find that you need to restore your whole system, as I did after making a mistake in the procedure! If you are not certain of your ability to dual boot your computer without disrupting your workflow, I recommend you skip ahead to the simpler solution: just stick with the Native OS and install what you need. In the case of Macintosh, you could start with VirtualBox, and then after you gain experience you may decide to get VMWare for a license fee. The price of VMWare could pale into insignificance compared with the time you may waste if you make a small mistake in the dual-boot process and need to wipe your hard disc drive and start again.telnet for High Sierra
High Sierra (10.13.2...) does not support telnet, although it has been supported in previous releases of macOS. In the real-world it is better to use Secure Shell, but in the GNS3 environment, telnet is fine. If your computer does not do ‘telnet’ you can copy a telnet binary to /usr/local/bin. If you have not yet upgraded to High Sierra, you will find a suitable telnet binary at /usr/bin on your Mac.Virtual Box
Virtual Box is not quite as effective for GNS3 as VMWare but has the advantage of being free, and is highly recommended as a starting point. Later you can decide whether you want to purchase VMWare or to dual boot Ubuntu. Go to https://www.virtualbox.org/ and follow the instructions.Wireshark for mac OS
Although it is not absolutely necessary, I recommend you download your own copy of Wireshark, for your own OS. Then you will be able to examine packet traces that have been previously collected and stored. Go to https://www.wireshark.org/ and click on “Download”. Follow the instructions to download and install Wireshark.