I like the idea of starting with the easy containers first.
Create a FileSystem
cd /var/lib/machines # create a directory mkdir <container> # use pacstrap to create a file system pacstrap -i -c -d <container> base --ignore linux
At this point you might want to copy over some configs to save time later.
First boot and create root password
systemd-nspawn -b -D <container> passwd # assuming you copied over /etc/locale.gen locale-gen # set timezone timedatectl set-timezone <timezone> # enable network time timedatectl set-ntp 1 # enable networking systemctl enable systemd-networkd systemctl enable systemd-resolved poweroff # if you want to nat the container add *-n* flag systemd-nspawn -b -D <container> -n # and to bind mount the package cache systemd-nspawn -b -D <container> -n --bind=/var/cache/pacman/pkg
Here's a link that skips ahead to Automatically Starting the Container
On Arch, assuming you have systemd-networkd and systemd-resolved
set up correctly, networking from the host end of things should
However on Linode it does not. What does work on Linode is to create a bridge interface. Two files for br0 will get the job done.
# /etc/systemd/network/50-br0.netdev [NetDev] Name=br0 Kind=bridge
# /etc/systemd/network/50-br0.netdev [Match] Name=br0 [Network] Address=10.0.55.1/24 # arbitrarily pick a subnet range to taste DHCPServer=yes IPMasquerade=yes
Notice how the configuration file tells systemd-networkd to offer
DHCP service and to perform masquerade. You can modify the
command to use the bridge interface. Every container attached to this bridge
will be on the same subnet and able to talk to each other.
# first restart systemd-networkd to bring up the new bridge interface systemctl restart systemd-networkd # and add --network-bridge=br0 to systemd-nspawn command systemd-nspawn -b -D <container> --network-bridge=br0 --bind=/var/cache/pacman/pkg
Automatically Starting the Container
Here's a link back up to Networking in case you previously skipped ahead.
There are two ways to automate starting the container. You can override
systemd-nspawn@.service or create an nspawn file.
First enable machines.target
# to override the systemd-nspawn@.service file cp /lib/systemd/system/systemd-nspawn@.service /etc/systemd/system/systemd-nspawn@<container>.service
/etc/systemd/system/systemd-nspawn@<container>.service to add the
you want to the
# /etc/systemd/nspawn/<container>.nspawn [Files] Bind=/var/cache/pacman/pkg [Network] Bridge=br0
# /etc/systemd/nspawn/<container>.nspawn [Files] Bind=/var/cache/pacman/pkg [Network] VirtualEthernet=1 # this seems to be the default sometimes, though
# in either case systemctl start/enable systemd-nspawn@<container> # to get a shell machinectl shell <container> # and then to get an environment bash
This would be a good time to check for network and name resolution, symlink resolv.conf if need be.
Initial Configuration Inside The Container
# set time zone if you don't want UTC timedatectl set-timezone <timezone> # enable ntp, networktime timedatectl set-ntp 1 # enable networking from inside the container systemctl enable systemd-networkd systemctl start systemd-networkd systemctl enable systemd-resolved systemctl start systemd-resolved rm /etc/resolv.conf ln -s /run/systemd/resolve/resolv.conf /etc/ # ping google ping -c 3 google.com
- You can start/stop nspawn containers with
- You can start nspawn containers with
- You can configure the systemd service for a container with @nspawn.service file override
- Or you can configure an nspawn container with a dot.nspawn file
But in regards to the above list I have noticed differences in behaviour, in some scenarios, concerning file attributes for bind mounts.
Another curiosity: when you have nspawn containers natted on VirtualEthernet connections, they might be able to ping each other at 10.x.y.z, but not resolve each other. But they might be able to resolve each other if they are all connected to the same bridge interface or nspawn network zone, but will randomly resolve each other in any of the 10.x.y.z, 169.x.y.z, or fe80::....:....:....%host (ipv6 local) spaces, which would complicate configuring the containers to talk to each other. But I intend to look into this some more.