How to Install OpenShift 4.9 on Bare Metal (UPI)

Hello Techies, as you know Openshift provides container platform and can installed either on onprem or in public cloud using different methods like IPI (Installer Provisioned Installer), UPI (User Provisioned Infrastructure) and Assisted Bare Metal installer.

In this post, we will demonstrate how to install Openshift 4.9 on bare metal nodes with UPI approach.

For the demonstration purpose, I am using KVM virtual machines. Following are my lab setup details,

Total Virtual Machines: 7

Bastion Node:  

  • OS – Rocky Linux 8 / CentOS 8,
  • RAM- 4GB, vPCU-4,
  • Disk- 120 GB
  • Network: Management N/w – (169.144.104.228), ocp internal n/w – (192.168.110.115)

Bootstrap Node:

  • OS : Core OS
  • RAM : 8GB
  • vCPU: 4
  • Disk: 40 GB
  • Network: OCP Internal Network (192.168.110.116)

Control Plane 1 Node:

  • OS : Core OS
  • RAM : 10GB
  • vCPU: 6
  • Disk: 60 GB
  • Network: OCP Internal Network (192.168.110.117)

Control Plane 2 Node:

  • OS : Core OS
  • RAM : 10GB
  • vCPU: 6
  • Disk: 60 GB
  • Network: OCP Internal Network (192.168.110.118)

Control Plane 3 Node:

  • OS : Core OS
  • RAM : 10GB
  • vCPU: 6
  • Disk: 60 GB
  • Network: OCP Internal Network (192.168.110.119)

Worker Node 1:

  • OS : Core OS
  • RAM : 12GB
  • vCPU: 8
  • Disk: 60 GB
  • Network: OCP Internal Network (192.168.110.120)

Worker Node 2:

  • OS : Core OS
  • RAM : 12GB
  • vCPU: 8
  • Disk: 60 GB
  • Network: OCP Internal Network (192.168.110.121)

Note: In KVM hypervisor, we have created host only network for ocp-internal.

Use the following file and commands to create host only network in KVM,

$ cat hostonly.xml
<network>
  <name>hostnet</name>
  <bridge name='virbr2' stp='on' delay='0'/>
  <ip address='192.168.110.1' netmask='255.255.255.0'>
      <range start='192.168.110.10' end='192.168.110.254'/>
  </ip>
</network>
$ sudo virsh net-define hostonly.xml
$ virsh net-start hostnet
$ virsh net-autostart hostnet
$ sudo systemctl restart libvirtd

Download Openshift Software from Red Hat portal

a)    Login to Red Hat Portal using following URL:

https://cloud.redhat.com/openshift

b)    Click on Create Cluster

c)     Choose Datacenter Tab –> Click on BareMetal

d)    Select the Installation Type as ‘UPI’ (User-provisioned infrastructure)

e)    Download the followings

  • OpenShift Installer
  • Pull Secret
  • Command Line Interface
  • RHCOS ISO
  • RHCOS RAW

Download-OpenShift-Software

Download-OCP-RHCOS-ISO-RAW

Let’s now jump into the installation steps of OpenShift

Step 1) Prepare Bastion Node

Create a virtual machine with resources mentioned above for bastion, you can install OS either Rocky Linux 8 or CentOS 8.  Assign the ip address from management and ocp internal network.

Similarly create bootstrap, control plane VMs and Worker VMs and attach OCP network (hostnet) to interface and note down their mac address. So, in my case following are the MAC addresses,

  • Bootstrap:  52:54:00:bf:60:a3
  • ocp-cp1: 52:54:00:98:49:40
  • ocp-cp2: 52:54:00:fe:8a:7c
  • ocp-cp3: 52:54:00:58:d3:31
  • ocp-w1: 52:54:00:38:8c:dd
  • ocp-w2: 52:54:00:b8:84:40

Step 2) Configure Services on bastion node

Transfer the downloaded Openshift software including the secret to bastion node under the root folder.

OpenShift-Software-Required

Extract openshift client tar file using following tar command,

# tar xvf openshift-client-linux.tar.gz
# mv oc kubectl /usr/local/bin

Confirm openshift client tool installation and its version by running,

# oc version
# kubectl version

Output of above command would look like below:

Openshift-Client-Version

Extract Openshift Installer tar file,

# tar xpvf openshift-install-linux.tar.gz
README.md
openshift-install
#

Configure Zones and masquerading (SNAT)

In my bastion node, I have two lan cards, ens3 and ens8. On ens3 , external or management network is configured and on ens8, ocp internal network is configured. So, define the following zones and enable masquerading on both the zones.

# nmcli connection modify ens8 connection.zone internal
# nmcli connection modify ens3 connection.zone external
# firewall-cmd --get-active-zones
# firewall-cmd --zone=external --add-masquerade --permanent
# firewall-cmd --zone=internal --add-masquerade --permanent
# firewall-cmd --reload

Verify the zone settings by running following firewall-cmd commands,

# firewall-cmd --list-all --zone=internal
# firewall-cmd --list-all --zone=external

Zone-Settings-firewall-cmd

Now let’s configure DNS, DHCP, Apache, HAProxy and NFS Service.

Note: For the demonstration purpose, I am using ‘linuxtechi.lan’ as the base domain.

Configure DNS Server

To install DNS server and its dependencies, run following dnf command

# dnf install bind bind-utils -y

Edit /etc/named.conf and make sure file has the following contents,

# vi /etc/named.conf

ocp-dns-linux

ocp-dns-domain-zone

Now create forward and reverse zone file,

# mkdir /etc/named/zones
# vi /etc/named/zones/db.linuxtechi.lan

DNS-Records-Zone-File

Save and exit the file.

Create reverse zone file with following entries,

# vi /etc/named/zones/db.reverse

reverse-zone-dns-records

Save and close the file and then start & enable dns service

# systemctl start named
# systemctl enable named

Allow the DNS port in firewall, run

# firewall-cmd --add-port=53/udp --zone=internal --permanent
# firewall-cmd --reload

Configure DHCP Server 

Install and configure the dhcp server, bind the mac address of bootstrap, control planes and worker nodes to their respective IPs. Run below command to install dhcp package,

# dnf install -y dhcp-server

Edit the /etc/dhcp/dhcpd.conf file and add the following contents, use the mac addresses that we have collected in step1 and specify the IP address of nodes according the DNS entries. So in my case, content of file will look like below,

[[email protected] ~]# vi /etc/dhcp/dhcpd.conf
authoritative;
ddns-update-style interim;
allow booting;
allow bootp;
allow unknown-clients;
ignore client-updates;
default-lease-time 14400;
max-lease-time 14400;
subnet 192.168.110.0 netmask 255.255.255.0 {
 option routers                  192.168.110.215; # lan
 option subnet-mask              255.255.255.0;
 option domain-name              "linuxtechi.lan";
 option domain-name-servers       192.168.110.215;
 range 192.168.110.216 192.168.110.245;
}

host ocp-bootstrap {
 hardware ethernet 52:54:00:bf:60:a3;
 fixed-address 192.168.110.216;
}

host cp1 {
 hardware ethernet 52:54:00:98:49:40;
 fixed-address 192.168.110.217;
}

host cp2 {
 hardware ethernet 52:54:00:fe:8a:7c;
 fixed-address 192.168.110.218;
}

host cp3 {
 hardware ethernet 52:54:00:58:d3:31;
 fixed-address 192.168.110.219;
}

host w1 {
 hardware ethernet 52:54:00:38:8c:dd;
 fixed-address 192.168.110.220;
}

host w2 {
 hardware ethernet 52:54:00:b8:84:40;
 fixed-address 192.168.110.221;
}

DHCP-file-Contents

Save and close the file.

Start DHCP service and allow dhcp service for internal zone in firewall, run

[[email protected] ~]# systemctl start dhcpd
[[email protected] ~]# systemctl enable dhcpd
[[email protected] ~]# firewall-cmd --add-service=dhcp --zone=internal --permanent
success
[[email protected] ~]# firewall-cmd --reload
success
[[email protected] ~]#

Configure Apache Web Server

We need apache to serve ignition and rhcos file, so let’s first install it using below command,

[[email protected] ~]# dnf install -y  httpd

Change the default apache listening port from 80 to 8080 by running beneath sed command

[[email protected] ~]# sed -i 's/Listen 80/Listen 0.0.0.0:8080/' /etc/httpd/conf/httpd.conf

Start and enable apache service via below command,

[[email protected] ~]# systemctl start httpd
[[email protected] ~]# systemctl enable httpd

Allow Apache service port (8080) for internal zone,

[[email protected] ~]# firewall-cmd --add-port=8080/tcp --zone=internal --permanent
[[email protected] ~]# firewall-cmd --reload

Configure HAProxy

We will use haproxy to load balance the Openshift services like ectd, ingress http & ingress https and apps like openshift console.

So, let’s first install haproxy by running following dnf command,

[[email protected] ~]#  dnf install -y haproxy

Edit haproxy confile and add the following contents to it

[[email protected] ~]# vi /etc/haproxy/haproxy.cfg
# Global settings
#---------------------------------------------------------------------
global
    maxconn     20000
    log         /dev/log local0 info
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    user        haproxy
    group       haproxy
    daemon
    # turn on stats unix socket
    stats socket /var/lib/haproxy/stats
#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
    log                     global
    mode                    http
    option                  httplog
    option                  dontlognull
    option http-server-close
    option redispatch
    option forwardfor       except 127.0.0.0/8
    retries                 3
    maxconn                 20000
    timeout http-request    10000ms
    timeout http-keep-alive 10000ms
    timeout check           10000ms
    timeout connect         40000ms
    timeout client          300000ms
    timeout server          300000ms
    timeout queue           50000ms

# Enable HAProxy stats
listen stats
    bind :9000
    stats uri /stats
    stats refresh 10000ms

# Kube API Server
frontend k8s_api_frontend
    bind :6443
    default_backend k8s_api_backend
    mode tcp

backend k8s_api_backend
    mode tcp
    balance source
    server      ocp-bootstrap 192.168.110.216:6443 check
    server      cp1 192.168.110.217:6443 check
    server      cp2 192.168.110.218:6443 check
    server      cp3 192.168.110.219:6443 check

# OCP Machine Config Server
frontend ocp_machine_config_server_frontend
    mode tcp
    bind :22623
    default_backend ocp_machine_config_server_backend

backend ocp_machine_config_server_backend
    mode tcp
    balance source
    server      ocp-bootstrap 192.168.110.216:22623 check
    server      cp1 192.168.110.217:22623 check
    server      cp2 192.168.110.218:22623 check
    server      cp3 192.168.110.219:22623 check

# OCP Ingress - layer 4 tcp mode for each. Ingress Controller will handle layer 7.
frontend ocp_http_ingress_frontend
    bind :80
    default_backend ocp_http_ingress_backend
    mode tcp

backend ocp_http_ingress_backend
    balance source
    mode tcp
    server cp1 192.168.110.217:80 check
    server cp2 192.168.110.218:80 check
    server cp3 192.168.110.219:80 check
    server w1 192.168.110.220:80 check
    server w2 192.168.110.221:80 check

frontend ocp_https_ingress_frontend
    bind *:443
    default_backend ocp_https_ingress_backend
    mode tcp

backend ocp_https_ingress_backend
    mode tcp
    balance source
    server cp1 192.168.110.217:443 check
    server cp2 192.168.110.218:443 check
    server cp3 192.168.110.219:443 check
    server w1 192.168.110.220:443 check
    server w2 192.168.110.221:443 check

save and exit the file.

Start and enable haproxy to make above changes into the effect

[[email protected] ~]# setsebool -P haproxy_connect_any 1
[[email protected] ~]# systemctl start haproxy
[[email protected] ~]# systemctl enable haproxy

Allow HAProxy ports that we have defined in its configuration file in OS firewall. Run beneath commands,

[[email protected] ~]# firewall-cmd --add-port=6443/tcp --zone=internal --permanent
[[email protected] ~]# firewall-cmd --add-port=6443/tcp --zone=external --permanent
[[email protected] ~]# firewall-cmd --add-port=22623/tcp --zone=internal --permanent
[[email protected] ~]# firewall-cmd --add-service=http --zone=internal --permanent
[[email protected] ~]# firewall-cmd --add-service=http --zone=external --permanent
[[email protected] ~]# firewall-cmd --add-service=https --zone=internal --permanent
[[email protected] ~]# firewall-cmd --add-service=https --zone=external --permanent
[[email protected] ~]# firewall-cmd --add-port=9000/tcp --zone=external --permanent
[[email protected] ~]# firewall-cmd --reload
[[email protected] ~]#

Configure NFS Server

We need NFS server to provide the persistent storage to OpenShift registry.

Run following command to install nfs server,

[[email protected] ~]# dnf install nfs-utils -y

Create following directory and set the required permissions.  This directory will be exported as NFS share,

[[email protected] ~]# mkdir -p /shares/registry
[[email protected] ~]# chown -R nobody:nobody /shares/registry
[[email protected] ~]# chmod -R 777 /shares/registry

Now export the share by adding the following line to /etc/exports file.

[[email protected] ~]# vi /etc/exports
/shares/registry  192.168.110.0/24(rw,sync,root_squash,no_subtree_check,no_wdelay)

Save and close the file and run ‘exportfs -rv’ to export the directory

[[email protected] ~]# exportfs -rv
exporting 192.168.110.0/24:/shares/registry
[[email protected] ~]#

Start and enable NFS service

[[email protected] ~]# systemctl start nfs-server rpcbind nfs-mountd
[[email protected] ~]# systemctl enable nfs-server rpcbind

Allow NFS service in OS firewall, run following commands,

[[email protected] ~]# firewall-cmd --zone=internal --add-service mountd --permanent
[[email protected] ~]# firewall-cmd --zone=internal --add-service rpc-bind --permanent
[[email protected] ~]# firewall-cmd --zone=internal --add-service nfs --permanent
[[email protected] ~]# firewall-cmd --reload

Step 3) Generate Manifests and Ignition files

To generate ignition files for bootstrap, control plane and worker nodes, refer the following steps

a)    Generate SSH keys

[[email protected] ~]# ssh-keygen

Generate-ssh-keys-linux

These ssh keys will be used to remotely access the bootstrap, control plane and worker nodes.

b)    Create install-config.yaml file with following contents

[[email protected] ~]# vi /ocp-install/install-config.yaml
apiVersion: v1
baseDomain: linuxtechi.lan        #base domain name
compute:
  - hyperthreading: Enabled
    name: worker
    replicas: 0 # Must be set to 0 for User Provisioned Installation as worker nodes will be manually deployed.
controlPlane:
  hyperthreading: Enabled
  name: master
  replicas: 3
metadata:
  name: lab # Cluster name
networking:
  clusterNetwork:
    - cidr: 10.128.0.0/14
     hostPrefix: 23
  networkType: OpenShiftSDN
  serviceNetwork:
    - 172.30.0.0/16

platform:
  none: {}
fips: false
pullSecret: '{"auths": ...}'           # Copy the pullsecret here
sshKey: "ssh-ed25519 AAAA..."          # Copy ssh public key here

In Line 23 and 24 copy contents of pull secret and public key that we generated above.

After making the changes file will look like below:

OpenShift-Install-Config-yaml-file

c)   Generate manifests file

Run following openshift-install command,

[[email protected] ~]# ~/openshift-install create manifests --dir ~/ocp-install

create -k8s-manifests-file-openshift

Above warning message says that master nodes are schedulable, it means we can have workload on control planes (control planes will also work as worker nodes). If you wish to disable this then run following sed command,

# sed -i 's/mastersSchedulable: true/mastersSchedulable: false/' ~/ocp-install/manifests/cluster-scheduler-02-config.yml

Note: In my case, I am not disabling it.

d)    Generate Ignition and auth file

Run beneath openshift-install command,

[[email protected] ~]# ~/openshift-install create ignition-configs --dir ~/ocp-install/

Output,

Ignition-auth-files-openshift

e)    Serve Manifests, ignition and core OS image file via web server

Create /var/www/html/ocp4 directory and copy all the files from ‘/root/ocp-install’ to ocp4.

[[email protected] ~]# mkdir /var/www/html/ocp4
[[email protected] ~]# cp -R ~/ocp-install/* /var/www/html/ocp4
[[email protected] ~]# mv ~/rhcos-metal.x86_64.raw.gz /var/www/html/ocp4/rhcos

Set the required permissions on ocp4 directory

[[email protected] ~]# chcon -R -t httpd_sys_content_t /var/www/html/ocp4/
[[email protected] ~]# chown -R apache: /var/www/html/ocp4/
[[email protected] ~]# chmod 755 /var/www/html/ocp4/

Verify whether these files are accessible or not via curl command

[[email protected] ~]# curl 192.168.110.215:8080/ocp4/

Output should look like below

ocp4-curl-command-verify

Perfect, now we are ready to start deployment.

Step 4) Start OpenShift deployment

Boot the bootstrap VM with rhcos-live ISO file. We will get the following screen

RHEL-Core-OS-Screen

When it boots up with the ISO file, we will get the following screen,

Coreos-installer-bootstrap-openshift

Type coreos-installer command and hit enter

$ sudo coreos-installer install /dev/sda --insecure --image-url http://192.168.110.215:8080/ocp4/rhcos  --ignition-url http://192.168.110.215:8080/ocp4/bootstrap.ign --insecure-ignition

Once the installation is completed, we will get the following screen,

Download-rhcos-bootstrap-deployment

Reboot the bootstrap node so that it boots up with hard disk this time.

$ sudo reboot

Similarly boot all three-control plane nodes with RHEL Core OS (rhcos) ISO file. Once control nodes boot up then run the following command and hit enter

$ sudo coreos-installer install /dev/sda --insecure --image-url http://192.168.110.215:8080/ocp4/rhcos  --ignition-url http://192.168.110.215:8080/ocp4/master.ign --insecure-ignition

Coreos-installer-master-openshift

Reboot the control plane and boot it with hard disk.

Repeat this procedure for rest of control planes and monitor bootstrap process using following command.

[[email protected] ~]# ~/openshift-install --dir ~/ocp-install wait-for bootstrap-complete --log-level=debug

Now, boot both the worker nodes with Core OS ISO file and once it boots up then run following command on the nodes

$ sudo coreos-installer install /dev/sda --insecure --image-url http://192.168.110.215:8080/ocp4/rhcos  --ignition-url http://192.168.110.215:8080/ocp4/worker.ign --insecure-ignition

Bootstrap process for control planes and worker nodes may take 10 to 15 minutes depending on your infrastructure. Check status of nodes by using following commands

[[email protected] ~]# export KUBECONFIG=~/ocp-install/auth/kubeconfig
[[email protected] ~]# oc get nodes
NAME                     STATUS   ROLES           AGE   VERSION
cp1.lab.linuxtechi.lan   Ready    master,worker   69m   v1.22.0-rc.0+894a78b
cp2.lab.linuxtechi.lan   Ready    master,worker   66m   v1.22.0-rc.0+894a78b
cp3.lab.linuxtechi.lan   Ready    master,worker   68m   v1.22.0-rc.0+894a78b
[[email protected] ~]#

Now approve all the pending CSR for the worker nodes so that they can join cluster and become ready. Run following oc command to view pending CSR

[[email protected] ~]# oc get csr

Run following oc command to approve the pending CSRs

[[email protected] ~]# oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs oc adm certificate approve

Output of above two commands would look like below:

Approve-Pending-CSR-Oc-Command

After couple of minutes, worker nodes should join the cluster and should be in ready state, run beneath commands to confirm the same.

[[email protected] ~]# oc get nodes

OC-Nodes-Status-OpenShift-Cluster

Great, above confirms that both worker nodes join the cluster and are in ready state.

Also check the status of bootstrap and in the output we should get the following,

[[email protected] ~]# ~/openshift-install --dir ~/ocp-install wait-for bootstrap-complete --log-level=debug

Bootstrap-Status-OpenShift

Above confirms that bootstrap process is also completed, and we are good to stop and delete bootstrap VM resources and bootstrap entries from haproxy file.

This conclude the article; I hope you find it informative. Please do share your feedback and comments.

Also Read : How to Setup Single Node OpenShift Cluster on RHEL 8

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