Installation ============ To install Incus with support for creating both containers and virtual machines, run: sudo apt install incus If you only wish to create containers in Incus and don't want the additional dependencies required for running virtual machines, you can install just the base package: sudo apt install incus-base Incus initialization ==================== If you wish to migrate existing containers or VMs from LXD, please refer to the next section. Otherwise, after installing Incus you must perform an initial configuration: sudo incus admin init Migrating from LXD ================== Incus includes a tool named `lxd-to-incus`, included in the "incus-extra" package, which can be used to convert an existing LXD installation into an Incus one. For this to work properly, you should install Incus but not initialize it. Instead, make sure that both `incus info` and `lxc info` both work properly, then run `lxd-to-incus` to migrate your data. This process transfers the entire database and all storage from LXD to Incus, resulting in an identical setup after the migration. For further information, please visit https://linuxcontainers.org/incus/docs/main/howto/server_migrate_lxd/ WARNING: This should be considered a destructive action from LXD's perspective. Afterwards the LXD daemon may not properly start, and running `lxc list` will be empty. It is recommend that the LXD packages be purged as part of running `lxd-to-incus`, or by hand immediately following the migration. Configuration ============= Incus's default bridge networking requires the dnsmasq-base package to be installed. If you chose to install Incus without its recommended packages and intend to use the default bridge, you must first install dnsmasq-base for networking to work correctly. If you wish to allow non-root users to interact with Incus via the local Unix socket, you must add them to the incus group: sudo usermod -aG incus Access via the incus group grants restricted access to Incus, allowing members to run most commands, except `incus admin`. For the vast majority of use cases, this is the preferred setup. Alternatively, if you wish to allow non-root users full administrative access to Incus via the local Unix socket, you must add them to the incus-admin group: sudo usermod -aG incus-admin From the upstream documentation (https://linuxcontainers.org/incus/docs/main/security/), be aware that local access to Incus through the Unix socket via the incus-admin group always grants full access to Incus. This includes the ability to attach file system paths or devices to any instance as well as tweak the security features on any instance. Therefore, you should only give access to users who would be trusted with root access to the host. Init scripts ============ systemd, SysV, and runit init scripts are provided, but the SysV and runit scripts aren't as well-tested as the systemd ones. Bug reports and patches are welcome to improve the Incus experience on non-systemd installs. Non-systemd required configuration ---------------------------------- When installing Incus on a non-systemd host, you must ensure that a cgroup v2 hierarchy is mounted prior to starting Incus. One possible way to do this is to add a line like the following to your /etc/fstab: cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec 0 0 Additionally, the "incus-user" service is not automatically started after install to allow the local administrator to first run `incus admin init`. After performing initialization, you can then enable/start the "incus-user" service. This is needed because if "incus-user" starts before Incus has been configured it will create a minimal empty profile which then conflicts with running `incus admin init`. (Hosts running systemd avoid this by relying on socket-based activation for the "incus" and "incus-user" services.) Logging ======= By default, the Incus daemon will log to /var/log/incus/incus.log. If you wish to log instead to the host system's configured rsyslog daemon, set USE_SYSLOG=yes in /etc/default/incus and restart the service. When using the runit scripts, Incus logs will always be written to /var/log/runit/incus/current. Storage backends ================ Incus supports several storage backends. When installing, Incus will suggest the necessary packages to enable all storage backends, but in brief: * btrfs requires the btrfs-progs package * ceph/cephfs require the ceph-common package * lvm requires the lvm2 package * zfs requires the zfsutils-linux package After installing one or more of those additional packages, be sure to restart the Incus service so it picks up the additional storage backend(s). Virtual machines ================ Incus optionally can create virtual machine instances that match the host's architecture utilizing QEMU. To enable this capability, on the host system ensure that the "incus" package is installed and then restart the Incus service. You will now be able to create virtual machine instances by passing the `--vm` flag in your creation command. RHEL8/9 (and derivatives) ------------------------- RHEL8/9 do not ship the 9p kernel module, which is used to dynamically mount instance-specific agent configuration and the incus-agent binary into VMs. To work around this, Incus 0.5.1 added a new agent drive, providing those files through what looks like a CD-ROM drive rather than being retrieved over a networked filesystem. For example, to run CentOS 9-Stream, one now needs to do: incus create images:centos/9-Stream centos --vm incus config device add centos agent disk source=agent:config incus start centos For further details, please see the Incus 0.5.1 release notes (https://discuss.linuxcontainers.org/t/incus-0-5-1-has-been-released/18848). Known issues ============ * Running Incus and Docker on the same host can cause connectivity issues. A common reason for these issues is that Docker sets the FORWARD policy to DROP, which prevents Incus from forwarding traffic and thus causes the instances to lose network connectivity. There are two different ways you can fix this: - As outlined in bug #865975, message 91, you can add `net.ipv4.ip_forward=1` to /etc/sysctl.conf which will create a FORWARD policy that docker can use. Docker then won't set the FORWARD chain to DROP when it starts up. - Alternately, you can use the following command to explicitly allow network traffic from your network bridge to your external network interface: `iptables -I DOCKER-USER -i -o -j ACCEPT` (from the upstream Incus documentation at https://linuxcontainers.org/incus/docs/main/howto/network_bridge_firewalld/) * If the apparmor package is not installed on the host system, containers will fail to start unless their configuration is modified to include `lxc.apparmor.profile=unconfined`; this has been reported upstream at https://github.com/lxc/lxc/issues/4150.