Lately I have been playing around with LXD containers, and its actually pretty cool.

Lets create a new container:

lxc-create -t download -n TestCont

This will download the default Ubuntu image from the official repository and create a container named TestCont.

Fire it up with “lxc-start -n TestCont”, connect to it with “lxc-attach -n TestCont”. Now you are in the shell of your new container.

Install dnsmasq, configure it for DHCP and DNS and assign IP’s to your containers based on Name or MAC address. The entry in the dnsmasq conf file should look something like this:

dhcp-host=TestCont,10.0.0.205

Lets create 10 new containers, have them set to autostart, fire them up, and watch the process go along:

for i in `seq 1 10`; do lxc-copy -n TestCont -N TestCont$i;echo “lxc.start.auto = 1” | tee -a .local/share/lxc/TestCont$i/config;lxc-start -n TestCont$i; done; watch -n 5 lxc-ls -f

Maybe we can also configure the dnsmasq at the same time:

for i in `seq 1 10`; do echo “dhcp-host=Cont$i,10.0.0.$i” | tee -a /etc/dnsmasq.d/static-hosts.conf;lxc-copy -n TestCont -N TestCont$i;echo “lxc.start.auto = 1” | tee -a .local/share/lxc/TestCont$i/config;lxc-start -n TestCont$i; done; watch -n 5 lxc-ls -f

As you can see my dnsmasq conf file is called static-hosts.conf. Now i got 10 new containers with fixed IP addresses in 5 minutes – thats cool 🙂

Before copying the original container I have some tips on what to install in it:

sshd
vim
bash-completion

You could do it like this:

lxc-execute -n TextCont apt install ssh vim bash-completion -y

Now you got a nice base image with ssh for remote access, vim for file editing and bash completion. This image will have a ~420 MB footprint.
Another option is to put your public SSH key in the base image, now where getting somewhere 🙂