On an Ubuntu 16.04 or later system with all updates, check you have snapd installed and run a test snap:

snap version
sudo snap install hello-world
hello-world

To install SONiC:

sudo snap install --devmode --edge sonic-lool

The switch model and port layout aren't automatically detected; to set the SONiC "HWSKU", use snap set and restart the services:

sudo snap set sonic-lool hwsku=wedge100-32x100G
sudo systemctl restart snap.sonic-lool.swss

These are the profiles currently available and their support status:

The default MAC address is the one of the management interface; to override it:

sudo snap set sonic-lool mac-address=xx:yy:zz:aa:bb:cc

To see the output of the various daemons, run:

sudo journalctl -u snap.sonic-lool.swss  -f

The included redis-cli wrapper sets up the proper socket connection; note that SONiC uses DB 1:

sudo sonic-lool.redis-cli PING
sudo sonic-lool.redis-cli -n 1 HLEN HIDDEN

To clear all of SONiC's state and start afresh:

sudo systemctl stop snap.sonic-lool.swss
sudo sonic-lool.redis-cli FLUSHALL
sudo systemctl start snap.sonic-lool.swss

This snap includes two backends, broadcom and p4, which allow selecting which set of binaries to run. To chose the p4 backend and restart the services:

sudo snap set sonic-lool backend=p4
sudo systemctl restart snap.sonic-lool.swss