CentOS 7
Sponsored Link

OpenShift Origin 3.7 : Add Nodes to a Cluster
2018/02/07
 
Add Nodes to an existing Cluster.
This example is based on the environment like follows.
On this tutotial, add a Compute Node [node03.srv.world (10.0.0.53)] as an example.
-----------+-----------------------------------------------------------+------------
           |10.0.0.30                    |10.0.0.51                    |10.0.0.52
+----------+-----------+      +----------+-----------+      +----------+-----------+
|  [  dlp.srv.world ]  |      | [ node01.srv.world ] |      | [ node02.srv.world ] |
|     (Master Node)    |      |    (Compute Node)    |      |    (Compute Node)    |
|     (Compute Node)   |      |                      |      |                      |
+----------------------+      +----------------------+      +----------------------+

[1] On the target Node to be added, Create the same user for Cluster administration with other nodes and also grant root privileges to him.
[root@node03 ~]#
useradd origin

[root@node03 ~]#
passwd origin

[root@node03 ~]#
echo -e 'Defaults:origin !requiretty\norigin ALL = (root) NOPASSWD:ALL' | tee /etc/sudoers.d/openshift

[root@node03 ~]#
chmod 440 /etc/sudoers.d/openshift

# if Firewalld is running, allow SSH

[root@node03 ~]#
firewall-cmd --add-service=ssh --permanent

[root@node03 ~]#
firewall-cmd --reload

[2] On the target Node to be added, install OpenShift Origin 3.7 repository and Docker. Next, create a volume group for Docker Direct LVM to setup LVM Thinpool like follows.
[root@node03 ~]#
yum -y install centos-release-openshift-origin37 docker
[root@node03 ~]#
vgcreate vg_origin01 /dev/sdb1

Volume group "vg_origin01" successfully created
[root@node03 ~]#
echo VG=vg_origin01 >> /etc/sysconfig/docker-storage-setup

[root@node03 ~]#
systemctl start docker

[root@node03 ~]#
systemctl enable docker

[3] On Master Node, login with an admin user of the Cluster and copy SSH public-key to the new Node.
[origin@dlp ~]$
vi ~/.ssh/config
# add new node

Host dlp
    Hostname dlp.srv.world
    User origin
Host node01
    Hostname node01.srv.world
    User origin
Host node02
    Hostname node02.srv.world
    User origin
Host node03
    Hostname node03.srv.world
    User origin

[origin@dlp ~]$
ssh-copy-id node03

[4] On Master Node, login with an admin user of the Cluster and run Ansible Playbook for scaleout the Cluster. For [/etc/ansible/hosts] file, Use the latest one when you setup or scaleout the Cluster.
[origin@dlp ~]$
sudo vi /etc/ansible/hosts
# add into OSEv3 section

[OSEv3:children]
masters
nodes
new_nodes

[OSEv3:vars]
ansible_ssh_user=origin
ansible_become=true
openshift_deployment_type=origin

openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/.htpasswd'}]
openshift_master_default_subdomain=apps.srv.world
openshift_docker_insecure_registries=172.30.0.0/16

[masters]
dlp.srv.world openshift_schedulable=true containerized=false

[etcd]
dlp.srv.world

[nodes]
dlp.srv.world openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node01.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'east'}" openshift_schedulable=true
node02.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'west'}" openshift_schedulable=true

# add definition for new node
[new_nodes]
node03.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'south'}" openshift_schedulable=true

[origin@dlp ~]$
ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-node/scaleup.yml


................
................

PLAY RECAP *********************************************************************
dlp.srv.world              : ok=43   changed=2    unreachable=0    failed=0
localhost                  : ok=12   changed=0    unreachable=0    failed=0
node01.srv.world           : ok=29   changed=2    unreachable=0    failed=0
node02.srv.world           : ok=29   changed=2    unreachable=0    failed=0
node03.srv.world           : ok=179  changed=68   unreachable=0    failed=0


INSTALLER STATUS ***************************************************************
Initialization             : Complete
Node Install               : Complete

# show status

[origin@dlp ~]$
oc get nodes

NAME               STATUS    AGE       VERSION
dlp.srv.world      Ready     1h        v1.7.6+a08f5eeb62
node01.srv.world   Ready     1h        v1.7.6+a08f5eeb62
node02.srv.world   Ready     1h        v1.7.6+a08f5eeb62
node03.srv.world   Ready     1m        v1.7.6+a08f5eeb62
[5] After finishing to add new Nodes, Open [/etc/ansible/hosts] again and move new definitions to existing [nodes] section like follows.
[origin@dlp ~]$
sudo vi /etc/ansible/hosts
# remove new_nodes

[OSEv3:children]
masters
nodes
new_nodes

[OSEv3:vars]
ansible_ssh_user=origin
ansible_become=true
openshift_deployment_type=origin

openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true', 'challenge': 'true', 'kind': 'HTPasswdPasswordIdentityProvider', 'filename': '/etc/origin/master/.htpasswd'}]
openshift_master_default_subdomain=apps.srv.world
openshift_docker_insecure_registries=172.30.0.0/16

[masters]
dlp.srv.world openshift_schedulable=true containerized=false

[etcd]
dlp.srv.world

[nodes]
dlp.srv.world openshift_node_labels="{'region': 'infra', 'zone': 'default'}"
node01.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'east'}" openshift_schedulable=true
node02.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'west'}" openshift_schedulable=true
node03.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'south'}" openshift_schedulable=true

# remove these [new_nodes] section and move definition to [nodes] section above
[new_nodes]
node03.srv.world openshift_node_labels="{'region': 'primary', 'zone': 'south'}" openshift_schedulable=true
[6] By the way, if you'd like to add Master Node, it's possible to configure the same way like follows.
[origin@dlp ~]$
sudo vi /etc/ansible/hosts
[OSEv3:children]
masters
nodes
new_masters

.....
.....

[new_masters]
master02.srv.world openshift_schedulable=true containerized=false

[origin@dlp ~]$
ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-master/scaleup.yml

Matched Content
 
Tweet