block/

README

Glusterblock Volume Provisioner for Kubernetes 1.5+

quay.io/external_storage/glusterblock-provisioner:latest

[TOC]

What is Gluster Block Provisioner ?

Gluster Block Provisioner is an external provisioner which dynamically provision gluster block volumes ( ISCSI volumes ) on demand. The persistent Volume Claim which has been requested with this external provisioner's identity ( for eg# gluster.org/glusterblock) will be served by this provisioner. This provisioner is capable of operating on couple of modes ( gluster-block and heketi).

gluster-block mode : This is an experimental or test mode on which the provisioner will directly talk to gluster-block utility or command line interface of gluster-block.

heketi mode : This is the recommended/supported mode on which the provisioner will talk to heketi's Block API to provision gluster block volumes.

Additional Reference: gluster-block heketi gluster-kubernetes

Build Gluster Block Provisioner and container image

If you want to build the container from source instead of pulling the docker image, please follow below steps:

Step 1: Build the provisioner binary

[root@localhost]# go build glusterblock-provisioner.go

Step 2: Build docker container image

[root@localhost]# docker build -t glusterblock-provisioner .

Start Kubernetes Cluster

Start glusterblock provisioner

The following example uses gluster.org/glusterblock as the identity for the instance and assumes kubeconfig is at /root/.kube. The identity should remain the same if the provisioner restarts. If there are multiple provisioners, each should have a different identity.

[root@localhost] docker run -ti -v /root/.kube:/kube -v /var/run/kubernetes:/var/run/kubernetes --privileged --net=host  glusterblock-provisioner  -master=http://127.0.0.1:8080 -kubeconfig=/kube/config -id=gluster.org/glusterblock

Create a glusterblock Storage Class

[root@localhost] kubectl create -f glusterblock-class.yaml

The available storage class parameter are listed below:

parameters:
    resturl: "http://127.0.0.1:8081"
    restuser: "admin"
    restsecretnamespace: "default"
    restsecretname: "heketi-secret"
    hacount: "3"
    chapauthenabled: "true"
    opmode: "gluster-block"
    blockmodeargs: "glustervol=blockmaster1,hosts=10.67.116.108"

Global parameters applicable for both modes:

• opmode: This value decide in which mode gluster block provisioner has to work.

• chapauthenabled: This value has to be set to true if we want to provision block volume with CHAP authentication enabled. This is an optional parameter.

• hacount: This is the count of number of paths to the block target server. This provide high availability via multipathing capability of iscsi. If there is a path failure, the I/Os will not be disturbed and will be served via another available paths.

Heketi Mode Parameters:

If provisioner want to operate on heketi mode, below args can be filled in storageclass accordingly.

• resturl : Gluster REST service/Heketi service url which provision gluster block volumes on demand. The general format should be IPaddress:Port and this is a mandatory parameter for GlusterFS dynamic provisioner. If Heketi service is exposed as a routable service in openshift/kubernetes setup, this can have a format similar to http://heketi-storage-project.cloudapps.mystorage.com where the fqdn is a resolvable heketi service url.

• restuser : Gluster REST service/Heketi user who has access to create volumes in the Gluster Trusted Pool.

• restsecretnamespace + restsecretname : Identification of Secret instance that contains user password to use when talking to Gluster REST service. These parameters are optional, empty password will be used when both restsecretnamespace and restsecretname are omitted. The provided secret must have type "gluster.org/glusterblock".

Gluster-Block Mode parameters:

If provisioner want to operate on gluster-block, below args are required to be filled in storageclass.

• blockmodeargs:

This mode requires glustervol name and hosts to be mentioned in , seperated values as shown below. This is a mandatory parameter to be filled in storage class parameter.

"glustervol=blockmaster1,hosts=10.67.116.108"

How to test:

Create a claim

[root@localhost]# kubectl create -f glusterblock-claim1.yaml
persistentvolumeclaim "claim1" created

[root@localhost]# kubectl get pvc
NAME      STATUS    VOLUME                                     CAPACITY   ACCESSMODES   STORAGECLASS   AGE
claim1    Bound     pvc-b7045edf-3a26-11e7-af53-c85b7636c232   1Gi        RWX           glusterblock   56s
[root@localhost]# kubectl get pv
NAME                                       CAPACITY   ACCESSMODES   RECLAIMPOLICY   STATUS    CLAIM            STORAGECLASS   REASON    AGE
pvc-b7045edf-3a26-11e7-af53-c85b7636c232   1Gi        RWX           Delete          Bound     default/claim1   glusterblock             46s

[root@localhost]# kubectl get pvc,pv
NAME         STATUS    VOLUME                                     CAPACITY   ACCESSMODES   STORAGECLASS   AGE
pvc/claim1   Bound     pvc-b7045edf-3a26-11e7-af53-c85b7636c232   1Gi        RWX           glusterblock   1m

NAME                                          CAPACITY   ACCESSMODES   RECLAIMPOLICY   STATUS    CLAIM            STORAGECLASS   REASON    AGE
pv/pvc-b7045edf-3a26-11e7-af53-c85b7636c232   1Gi        RWX           Delete          Bound     default/claim1   glusterblock             1m