k3s/examples/volumes/fibre_channel

Step 1. Setting up Fibre Channel Target

On your FC SAN Zone manager, allocate and mask LUNs so Kubernetes hosts can access them.

Step 2. Creating the Pod with Fibre Channel persistent storage

Once you have installed Fibre Channel initiator and new Kubernetes, you can create a pod based on my example fc.yaml. In the pod JSON, you need to provide targetWWNs (array of Fibre Channel target's World Wide Names), lun, and the type of the filesystem that has been created on the lun, and readOnly boolean.

Once your pod is created, run it on the Kubernetes master:

kubectl create -f ./your_new_pod.json

Here is my command and output:

# kubectl create -f examples/volumes/fibre_channel/fc.yaml
# kubectl get pods
NAME      READY     STATUS    RESTARTS   AGE
fcpd      2/2       Running   0          10m

On the Kubernetes host, I got these in mount output

#mount |grep /var/lib/kubelet/plugins/kubernetes.io
/dev/mapper/360a98000324669436c2b45666c567946 on /var/lib/kubelet/plugins/kubernetes.io/fc/500a0982991b8dc5-lun-2 type ext4 (ro,relatime,seclabel,stripe=16,data=ordered)
/dev/mapper/360a98000324669436c2b45666c567944 on /var/lib/kubelet/plugins/kubernetes.io/fc/500a0982991b8dc5-lun-1 type ext4 (rw,relatime,seclabel,stripe=16,data=ordered)

If you ssh to that machine, you can run docker ps to see the actual pod.

# docker ps
CONTAINER ID        IMAGE                                  COMMAND             CREATED             STATUS              PORTS               NAMES
090ac457ddc2        kubernetes/pause                       "/pause"            12 minutes ago      Up 12 minutes                           k8s_fcpd-rw.aae720ec_fcpd_default_4024318f-4121-11e5-a294-e839352ddd54_99eb5415   
5e2629cf3e7b        kubernetes/pause                       "/pause"            12 minutes ago      Up 12 minutes                           k8s_fcpd-ro.857720dc_fcpd_default_4024318f-4121-11e5-a294-e839352ddd54_c0175742   
2948683253f7        gcr.io/google_containers/pause:0.8.0   "/pause"            12 minutes ago      Up 12 minutes                           k8s_POD.7be6d81d_fcpd_default_4024318f-4121-11e5-a294-e839352ddd54_8d9dd7bf       

Multipath

To leverage multiple paths for block storage, it is important to perform the multipath configuration on the host. If your distribution does not provide /etc/multipath.conf, then you can either use the following minimalistic one:

defaults {
    find_multipaths yes
    user_friendly_names yes
}

or create a new one by running:

$ mpathconf --enable

Finally you'll need to ensure to start or reload and enable multipath:

$ systemctl enable multipathd.service
$ systemctl restart multipathd.service

Note: Any change to multipath.conf or enabling multipath can lead to inaccessible block devices, because they'll be claimed by multipath and exposed as a device in /dev/mapper/*.

Some additional informations about multipath can be found in the iSCSI documentation