The following Kubernetes versions have been tested in the continuous integration system for this version of Cilium:
Cilium requires a Linux kernel >= 4.9. See System Requirements for the full details on all systems requirements.
Enable CNI in Kubernetes¶
CNI - Container Network Interface is the plugin layer used by Kubernetes to
delegate networking configuration. CNI must be enabled in your Kubernetes
cluster in order to install Cilium. This is done by passing
--network-plugin=cni to kubelet on all nodes. For more information, see
the Kubernets CNI network-plugins documentation.
Mounted BPF filesystem¶
This step is required for production environments but optional for testing
and development. It allows the
cilium-agent to pin BPF resources to a
persistent filesystem and make them persistent across restarts of the agent.
If the BPF filesystem is not mounted in the host filesystem, Cilium will
automatically mount the filesystem but it will be unmounted and re-mounted when
the Cilium pod is restarted. This in turn will cause BPF resources to be
re-created which will cause network connectivity to be disrupted. Mounting the
BPF filesystem in the host mount namespace will ensure that the agent can be
restarted without affecting connectivity of any pods.
In order to mount the BPF filesystem, the following command must be run in the host mount namespace. The command must only be run once during the boot process of the machine.
mount bpffs /sys/fs/bpf -t bpf
A portable way to achieve this with persistence is to add the following line to
/etc/fstab and then run
mount /sys/fs/bpf. This will cause the
filesystem to be automatically mounted when the node boots.
bpffs /sys/fs/bpf bpf defaults 0 0
If you are using systemd to manage the kubelet, see the section Mounting BPFFS with systemd.
The Standard Installation relies on the etcd-operator to manage an
etcd cluster. In order for the etcd cluster to be available, the Cilium pod is
being run with
dnsPolicy: ClusterFirstWithHostNet in order for Cilium to be
able to look up Kubernetes service names via DNS. This creates a dependency on
kube-dns. If you would like to avoid running kube-dns, choose a different
installation method and remove the
dnsPolicy field from the
Enable automatic node CIDR allocation (Recommended)¶
Kubernetes has the capability to automatically allocate and assign a per node IP
allocation CIDR. Cilium automatically uses this feature if enabled. This is the
easiest method to handle IP allocation in a Kubernetes cluster. To enable this
feature, simply add the following flag when starting
This option is not required but highly recommended.