microcore-mininit - stripped down Tiny Core Linux
Tiny Core Linux (http://tinycorelinux.net) is a very small and efficient Linux distribution. But for use with GNS3 on a local Mac or Windows system it's still relative slow, the linux-microcore-6.4 image takes about 25 seconds to boot. The reason is, that the qemu on those systems uses the slow software virtualization.
microcore-mininit is a microcore variant with a stripped down initialization. Additionally the IPv6 kernel modules, iproute2 and nano are added. It boots in about 10s with the slow qemu of Mac / Windows.
But this results in a lower flexibility. For Linux (and GNS3 VM) the normal microcore linux or a docker VM are better alternatives.
Building the image
The image is downloadable from the GitHub releases area.
If you want to build it yourself, you need a linux system and install packer (https://www.packer.io) and qemu.
Then build the image with
rm -rf output-qemu packer build microcore-mininit.json
Install the image in GNS3
As the image should run on the local system, the image can't be installed as an appliance, it has to be installed manually.
- Copy the image to the GNS3/images/QEMU directory
- In GNS3 open the Qemu VM preferences
- With "New" start the Qemu VM template wizard
- Select "Run this Qemu VM on my local computer"
- Choose a name for the VM
- Select the Qemu binary (-i386 or -x86_64) and the RAM size
The RAM size can be as low as 64 MB
- Select the microcore-mininit.qcow2 disk image and finish the wizard
- Optionally modify the just created template
- Exit the preferences with "OK"