k3s/examples/iscsi/README.md

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# How to Use it?
Here is my setup to setup Kubernetes with iSCSI persistent storage. I use Fedora 21 on Kubernetes node.
Install iSCSI initiator on the node:
# yum -y install iscsi-initiator-utils
then edit */etc/iscsi/initiatorname.iscsi* and */etc/iscsi/iscsid.conf* to match your iSCSI target configuration.
I mostly follow these [instructions](http://www.server-world.info/en/note?os=Fedora_21&p=iscsi&f=2) to setup iSCSI initiator and these [instructions](http://www.server-world.info/en/note?os=Fedora_21&p=iscsi) to setup iSCSI target.
Once you have installed iSCSI initiator and new Kubernetes, you can create a pod based on my example *iscsi.json*. In the pod JSON, you need to provide *targetPortal* (the iSCSI target's **IP** address and *port* if not the default port 3260), target's *iqn*, *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:
#cluster/kubectl.sh create -f your_new_pod.json
Here is my command and output:
```console
# cluster/kubectl.sh create -f examples/iscsi/v1beta3/iscsi.json
# cluster/kubectl.sh get pods
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED
iscsi 172.17.0.5 iscsipd-ro kubernetes/pause fed-minion/10.16.154.75 <none> Running About a minute
iscsipd-rw kubernetes/pause
```
On the Kubernetes node, I got these in mount output
```console
#mount |grep kub
/dev/sdb on /var/lib/kubelet/plugins/kubernetes.io/iscsi/iscsi/10.16.154.81:3260/iqn.2014-12.world.server:storage.target1/lun/0 type ext4 (ro,relatime,stripe=1024,data=ordered)
/dev/sdb on /var/lib/kubelet/pods/4ab78fdc-b927-11e4-ade6-d4bed9b39058/volumes/kubernetes.io~iscsi/iscsipd-ro type ext4 (ro,relatime,stripe=1024,data=ordered)
/dev/sdc on /var/lib/kubelet/plugins/kubernetes.io/iscsi/iscsi/10.16.154.81:3260/iqn.2014-12.world.server:storage.target1/lun/1 type xfs (rw,relatime,attr2,inode64,noquota)
/dev/sdc on /var/lib/kubelet/pods/4ab78fdc-b927-11e4-ade6-d4bed9b39058/volumes/kubernetes.io~iscsi/iscsipd-rw type xfs (rw,relatime,attr2,inode64,noquota)
```
If you ssh to that machine, you can run `docker ps` to see the actual pod.
```console
# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
cc9bd22d9e9d kubernetes/pause:latest "/pause" 3 minutes ago Up 3 minutes k8s_iscsipd-rw.12d8f0c5_iscsipd.default.etcd_4ab78fdc-b927-11e4-ade6-d4bed9b39058_e3f49dcc
```
Run *docker inspect* and I found the Containers mounted the host directory into the their */mnt/iscsipd* directory.
```console
#docker inspect --format "\{\{\.Volumes\}\}" cc9bd22d9e9d
map[/mnt/iscsipd:/var/lib/kubelet/pods/4ab78fdc-b927-11e4-ade6-d4bed9b39058/volumes/kubernetes.io~iscsi/iscsipd-rw /dev/termination-log:/var/lib/kubelet/pods/4ab78fdc-b927-11e4-ade6-d4bed9b39058/containers/iscsipd-rw/cc9bd22d9e9db3c88a150cadfdccd86e36c463629035b48bdcfc8ec534be8615]
```