Difference between revisions of "OCP4-IPI-libvirt"

From p0f
Jump to: navigation, search
(Preparing the Software: cleanup steps)
(Creating Configuration Manually: ens3 vs enp0s3)
Line 647: Line 647:
 
     bootstrapProvisioningIP: 10.1.1.9
 
     bootstrapProvisioningIP: 10.1.1.9
 
     provisioningBridge: provbr0
 
     provisioningBridge: provbr0
     provisioningNetworkInterface: enp0s3
+
     provisioningNetworkInterface: ens3
 
     provisioningMACAddress: '52:54:00:00:fb:0f'
 
     provisioningMACAddress: '52:54:00:00:fb:0f'
 
     # This needs to be done to avoid nested virtualisation if provisioner is a VM.
 
     # This needs to be done to avoid nested virtualisation if provisioner is a VM.
Line 707: Line 707:
 
sshKey: "ssh-rsa ..."
 
sshKey: "ssh-rsa ..."
 
</pre>
 
</pre>
 +
 +
Somewhere between RHCOS 4.12 and 4.14 the network devices stopped using the PCI naming scheme (in VMs only?). Consequently, <code>NetworkManager-wait-online</code> will fail because it's looking for a device (<code>enp0s3</code>) that isn't there (it's now called <code>ens3</code>). Sure, it's got an ''altname'' of <code>enp0s3</code> but <code>NetworkManager</code> don't care.
 +
 +
<pre>
 +
$ ip ad sh enp0s3
 +
2: ens3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
 +
    link/ether 52:54:00:00:fa:13 brd ff:ff:ff:ff:ff:ff
 +
    altname enp0s3
 +
    inet 172.25.3.13/24 brd 172.25.3.255 scope global dynamic noprefixroute ens3
 +
      valid_lft 86083sec preferred_lft 86083sec
 +
    inet6 fe80::a30:57dd:ee31:e42e/64 scope link noprefixroute
 +
      valid_lft forever preferred_lft forever
 +
</pre>
 +
 +
In turn, that will break most of the rest of the installation. Go figure. Just call the interface <code>ens3</code> and move on.
  
 
== Installation ==
 
== Installation ==

Revision as of 20:49, 2 February 2024

Introduction

What I Assume

  • You know how OpenShift installation works and what the difference between IPI and UPI is.
  • You know about the OpenShift Machine API and various underlying mechanisms.
  • You understand the different types of network interfaces on Linux and different libvirt networks.
  • You are familiar and comfortable with NetworkManager and the nmcli tool.
  • You are familiar and comfortable with libvirt CLI and XML.
  • You are familiar and comfortable with qemu-img tool.
  • We are not talking about any firewall restrictions here - it is your responsibility to ensure traffic is not blocked.

Outcomes

The installation described is for a fully managed IPI running OpenShift Container Platform v4.14, initially with three master and two worker nodes.

At a later point, I will add a couple of steps needed to grow the cluster by one extra worker node.

OpenShift Container Platform IPI Installation Using Libvirt

Prerequisites

Hardware requirements for the cluster:

  • 136 GiB RAM (32 GiB per control plane, 20 GiB per compute node), max overcommit ratio of 1.5 (make sure enough swap is available)
  • 52 vCPUs (12 per control plane, 8 per compute node), max overcommit ratio of 1.3 (higher might work, but will slow down the installation horribly and may ultimately fail)
  • one physical network interface that will be used for the public bridged network
  • a physical or virtual network interface that will be used for the provisioning network bridge

Hardware requirements for the installation client (provisioner) machine:

  • a minimum of 8 GiB RAM and 4 CPUs
  • a network connection to both the public bridged network and the provisioning network

Due to the fact provisioner needs access to both networks, and the provisioning network in this guide is a virtual one, it might be best if you define the provisioner as a VM, with the same network interface settings as the control/compute nodes.

In the case you want to run the workloads spread across several hypervisor hosts, there are some extra steps, but nothing big. More on that in #Installation Spanning Multiple Hypervisors below.

Software artifacts needed on the provisioner host:

  • oc, the command line client, of the corresponding version - download from https://mirror.openshift.com/pub/openshift-v4/clients/ocp/
  • libvirt-client package is required for openshift-baremetal-install to be able to communicate to hypervisor(s)
  • ipmitool or some other IPMI client
  • a pull-secret file containing authentication credentials for OpenShift Container Platform registries - download from https://console.redhat.com/openshift/
  • an SSH keypair that can be used for accessing OpenShift nodes

IMPORTANT: The external IP addresses of cluster nodes must be assigned by your infrastructure DHCP server.

Host Configuration

Beyond the logical requirement of having libvirt installed and started, here are the other configuration details for the hypervisor.

Network Settings

First thing you definitely need to make sure of, is that IP forwarding is enabled.

$ sysctl net.ipv4.ip_forward
1

Linux network settings need to be configured to have two Linux bridges, a public and a private provisioning one.

  • public bridge, call it bridge0, needs to have the public network interface enslaved to it
  • private bridge, call it provbr0, can be a virtual bridge since it is only needed for the provisioning network, which is supposed to be isolated and without any infrastructure services (such as DHCP, DNS, etc.)

It would be wonderful if the bridges could be OpenVSwitch ones, but unfortunately the Terraform bundled with openshift-baremetal-install currently does not include an OpenVSwitch provider, so there's goodbye to that.

As an example, here is my host configuration.

Public bridge:

$ ip addr show bridge0
6: bridge0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 48:21:0b:57:0e:06 brd ff:ff:ff:ff:ff:ff
    inet 172.25.35.2/24 brd 172.25.35.255 scope global noprefixroute bridge0
       valid_lft forever preferred_lft forever
    inet6 fe80::4a21:bff:fe57:e06/64 scope link
       valid_lft forever preferred_lft forever

$ ip addr show enp86s0
2: enp86s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master bridge0 state UP group default qlen 1000
    link/ether 48:21:0b:57:0e:06 brd ff:ff:ff:ff:ff:ff

$ bridge link | grep "master bridge0"
2: enp86s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 master bridge0 state forwarding priority 32 cost 100

Provisioning bridge:

$ ip addr show provbr0
5: provbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether ce:70:26:9c:88:a4 brd ff:ff:ff:ff:ff:ff
    inet 10.1.1.2/24 brd 10.1.1.255 scope global noprefixroute provbr0
       valid_lft forever preferred_lft forever
    inet6 fe80::cc70:26ff:fe9c:88a4/64 scope link
       valid_lft forever preferred_lft forever

$ bridge link | grep "master provbr0"

Installation Spanning Multiple Hypervisors

If you want to have your cluster spanning multiple hypervisors, make sure there is also a VXLAN connection between all the provisioning bridges.

You can do that by creating a vxlan type interface, which is a slave connection of type bridge, and the master is set to provbr0. Choose any unique VXLAN ID, and make sure it is the same on all interconnected hosts.

As an example, here is one VXLAN interface connecting hypervisor A to B.

$ nmcli con show provbr0-vxlan10 | grep -E '^(connection|vxlan)' | grep -vE '(default|uuid|--|-1|unknown)'
connection.id:                          provbr0-vxlan10
connection.type:                        vxlan
connection.interface-name:              provbr0-vxlan10
connection.autoconnect:                 yes
connection.autoconnect-priority:        0
connection.timestamp:                   1703164860
connection.read-only:                   no
connection.master:                      provbr0
connection.slave-type:                  bridge
connection.gateway-ping-timeout:        0
vxlan.id:                               10
vxlan.local:                            172.25.35.2
vxlan.remote:                           172.25.35.3
vxlan.source-port-min:                  0
vxlan.source-port-max:                  0
vxlan.destination-port:                 4790
vxlan.tos:                              0
vxlan.ttl:                              0
vxlan.ageing:                           300
vxlan.limit:                            0
vxlan.learning:                         yes
vxlan.proxy:                            no
vxlan.rsc:                              no
vxlan.l2-miss:                          no
vxlan.l3-miss:                          no

And this is the corresponding VXLAN interface definition connecting host B to A.

$ nmcli con show  provbr0-vxlan10 | grep -E '^(connection|vxlan)' | grep -vE '(default|uuid|--|-1|unknown)'
connection.id:                          provbr0-vxlan10
connection.type:                        vxlan
connection.interface-name:              provbr0-vxlan10
connection.autoconnect:                 yes
connection.autoconnect-priority:        0
connection.timestamp:                   1697549049
connection.read-only:                   no
connection.master:                      provbr0
connection.slave-type:                  bridge
connection.gateway-ping-timeout:        0
vxlan.id:                               10
vxlan.local:                            172.25.35.3
vxlan.remote:                           172.25.35.2
vxlan.source-port-min:                  0
vxlan.source-port-max:                  0
vxlan.destination-port:                 4790
vxlan.tos:                              0
vxlan.ttl:                              0
vxlan.ageing:                           300
vxlan.limit:                            0
vxlan.learning:                         yes
vxlan.proxy:                            no
vxlan.rsc:                              no
vxlan.l2-miss:                          no
vxlan.l3-miss:                          no

In this case, bridge link will of course initially also show the provbr0-vxlan10 interface as a slave, and will not show empty as above.

$ bridge link | grep "master provbr0"
7: provbr0-vxlan10: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 master provbr0 state forwarding priority 32 cost 100

libvirt Settings

Your libvirt will of course need to know about those network bridges in order to be able to attach VMs to them.

For that, you will need two network definitions, looking a bit like the following XML. Make sure they are autostart for least headache.

$ sudo virsh net-dumpxml external
<network>
  <name>external</name>
  <uuid>whatever</uuid>
  <forward mode='bridge'/>
  <bridge name='bridge0'/>
</network>

$ sudo virsh net-dumpxml provisioning
<network>
  <name>provisioning</name>
  <uuid>whatever</uuid>
  <forward mode='bridge'/>
  <bridge name='provbr0'/>
</network>

Additionally, you want to ensure that the storage pool is big enough, but that is not directly related to the subject at hand.

$ sudo virsh pool-info default
Name:           default
UUID:           whatever
State:          running
Persistent:     yes
Autostart:      yes
Capacity:       250.92 GiB
Allocation:     0 GiB
Available:      250.92 GiB

VirtualBMC

The most important part of IPI facilitation is to be able to simulate a baseboard management controller for your VMs. libvirt obviously doesn't do this, but luckily there's a small bit of Python code that does, and it's called virtualbmc.

In most Python environments you can install it using pip3, just make sure pip3 is up-to-date first.

$ pip3 install --upgrade pip
...

$ pip3 install virtualbmc
...

This gives you /usr/local/bin/vbmcd which you can control using the following systemd unit:

[Unit]
Description=vbmcd
[Service]
Type=forking
ExecStart=/usr/local/bin/vbmcd
[Install]
WantedBy=multi-user.target

Put the above content into /etc/systemd/system/vbmcd.service, reload systemd, and enable/start the service.

$ sudo systemctl daemon-reload
$ sudo systemctl enable --now vbmcd

You now have the ability to associate a TCP port with a virtual machine defined on the hypervisor host, and have it simulate an IPMI BMC for that VM!

Virtual Machine Configuration

VM Definitions

The virtual machines need to be configured with sufficient amount of compute resources, as per #Prerequisites above.

This section ties into the #Network Settings section above. You need two bridges on your hypervisor(s), bridge0 and provbr0.

An example control plane node definition in libvirt XML would look like this:

<domain type='kvm'>
  <name>controlplane1</name>
  <memory unit='GiB'>32</memory>
  <currentMemory unit='GiB'>32</currentMemory>
  <vcpu placement='static'>12</vcpu>
  <os>
    <type arch='x86_64' machine='q35'>hvm</type>
    <boot dev='hd'/>
    <boot dev='network'/>
    <bootmenu enable='yes'/>
  </os>
  <features>
    <acpi/>
    <apic/>
  </features>
  <cpu mode='host-model' check='partial'>
    <model fallback='allow'/>
  </cpu>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>destroy</on_crash>
  <pm>
    <suspend-to-mem enabled='no'/>
    <suspend-to-disk enabled='no'/>
  </pm>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/controlplane1-vda.qcow2'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </disk>
    <controller type='usb' index='0' model='qemu-xhci' ports='15'/>
    <controller type='pci' index='0' model='pcie-root'/>
    <interface type='bridge'>
      <mac address='52:54:00:00:fb:11'/>
      <source bridge='provbr0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <interface type='bridge'>
      <mac address='52:54:00:00:fa:11'/>
      <source bridge='bridge0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
    </interface>
    <console type='pty'/>
    <channel type='unix'>
      <source mode='bind'/>
      <target type='virtio' name='org.qemu.guest_agent.0'/>
    </channel>
    <input type='tablet' bus='usb'/>
    <input type='mouse' bus='ps2'/>
    <input type='keyboard' bus='ps2'/>
    <graphics type='vnc' autoport='yes' listen='0.0.0.0'/>
    <video>
      <model type='virtio'/>
    </video>
    <memballoon model='virtio'/>
    <rng model='virtio'>
      <backend model='random'>/dev/urandom</backend>
    </rng>
  </devices>
</domain>

A couple of things to note:

  • the first network interface is attached to provbr0, and its PCI address is lower (0x03), causing it to be the PXE default device
  • the second network interface is attached to bridge0, and its PCI address is higher (0x09), making it the second interface (for external connections)
  • boot order is set to hard disk first, network second, which means the host will only PXE boot if the disk image is unbootable
  • the disk image needs to be 64GiB in size at the minimum, but you can make it larger and/or add more disk images if you intend to use the local storage operator

When configuring other nodes, simply remember to change the node name, disk image name, and MAC addresses to be unique. Adjust hardware resources accordingly for compute nodes.

IPMI BMC

What is important for OCP IPI to be able to perform the installation properly is to register each virtual machine with vbmcd and assign it with a port.

$ vbmc add --port=6211 controlplane1
$ vbmc list
+-------------------+---------+---------+------+
| Domain name       | Status  | Address | Port |
+-------------------+---------+---------+------+
| controlplane1     | down    | ::      | 6211 |
+-------------------+---------+---------+------+
$ vbmc start controlplane1
$ vbmc list
+-------------------+---------+---------+------+
| Domain name       | Status  | Address | Port |
+-------------------+---------+---------+------+
| controlplane1     | running | ::      | 6211 |
+-------------------+---------+---------+------+
$ sudo ss -aunp | grep 6211
UNCONN 0      0                        *:6211             *:*    users:(("vbmcd",pid=766290,fd=21))

There is no need to run the vbmc client as root as it is the daemon that is running as root and can see all the VMs accessible through the qemu:///system URL.

Of course there are options. For any VM you add, you can specify a custom set of IPMI admin credentials (options --username and --password, they default to admin and password), a custom libvirt URL and credentials if necessary (options --libvirt-uri, --libvirt-sasl-username, and --libvirt-sasl-password), and a custom IP address to listen on (defaults to all addresses, use option --address to restrict it).

$ vbmc show controlplane1
+-----------------------+-------------------+
| Property              | Value             |
+-----------------------+-------------------+
| active                | True              |
| address               | ::                |
| domain_name           | controlplane1     |
| libvirt_sasl_password | ***               |
| libvirt_sasl_username | None              |
| libvirt_uri           | qemu:///system    |
| password              | ***               |
| port                  | 6211              |
| status                | running           |
| username              | admin             |
+-----------------------+-------------------+

Once started (which just opens the port) you can test the BMC connection using ipmitool or similar.

$ ipmitool -I lanplus -H localhost -p 6211 -U admin -P password chassis status
System Power         : off
Power Overload       : false
Power Interlock      : inactive
Main Power Fault     : false
Power Control Fault  : false
Power Restore Policy : always-off
Last Power Event     :
Chassis Intrusion    : inactive
Front-Panel Lockout  : inactive
Drive Fault          : false
Cooling/Fan Fault    : false

That's it! We're ready to install OCP!

Installer Configuration

This is where it all comes together. You need to execute the steps in this section (and next) on the provisioner host, that is, a system that has access to both external and provisioning networks of the OpenShift cluster-to-be. The access need not be direct, it can be routed, but if you, as in our example, configured the provisioning network to be an isolated virtual bridge, you will be best off by creating an additional VM that is directly connected to both bridges.

Gathering the Bits Together

First step is to make sure the following artifacts are available:

  • oc
  • pull-secret
  • an SSH public key for compute node access

The global cluster network settings that we will need to configure are:

  • the parent DNS domain of the cluster (such as example.com)
  • the name of the cluster (concatenated with DNS domain, for example mycluster will become mycluster.example.com)
  • the provisioning network CIDR (in our case, it can be any IP address block not overlapping with the external network as the provisioning network is isolated)
  • from the external network address space, a designated:
    • API server VIP (api.mycluster.example.com should point to it)
    • ingress load balancer VIP (any host within apps.mycluster.example.com should resolve to it, usually via a wildcard record)

Additionally, you will need, for each node its:

  • node name
  • provisioning interface MAC address
  • IPMI BMC address and port
  • IPMI BMC credentials
  • the name of the provisioning interface as seen from within the VM (re #Virtual Machine Configuration above - since the PCI address of the interface is bus 0x0 slot 0x3 it will be named enp0s3)

As already said, DHCP address assignment to external interfaces is not managed by the installer. It must be handled by your infrastructure.

Preparing the Software

First, make sure your pull-secret file is on the provisioner.

$ ls -l pull-secret
-rw-r-----. 1 provisioner provisioner 2734 Oct 27 12:21 pull-secret

Then after downloading oc (if you didn't do that already)...

$ curl -OL https://mirror.openshift.com/pub/openshift-v4/clients/ocp/stable-4.14/openshift-client-linux.tar.gz
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 60.9M  100 60.9M    0     0  4287k      0  0:00:14  0:00:14 --:--:-- 5642k

$ tar xf openshift-client-linux.tar.gz oc

$ ./oc version
Client Version: 4.14.9
Kustomize Version: v5.0.1

$ sudo cp ./oc /usr/local/bin/oc
$ rm -f ./oc ./openshift-client-linux.tar.gz

...and optionally generating a bash completion file...

$ oc completion bash > oc.completion
$ sudo cp oc.completion /etc/bash_completion.d/oc
$ rm -f oc.completion
$ source /etc/bash_completion.d/oc

...you can use it to extract openshift-baremetal-install from the release image you intend to use.

$ curl -s https://mirror.openshift.com/pub/openshift-v4/clients/ocp/stable-4.14/release.txt | grep "Pull From:"
Pull From: quay.io/openshift-release-dev/ocp-release@sha256:f5eaf0248779a0478cfd83f055d56dc7d755937800a68ad55f6047c503977c44

$ oc adm release extract --registry-config=pull-secret --command=openshift-baremetal-install --to=. \
    quay.io/openshift-release-dev/ocp-release@sha256:f5eaf0248779a0478cfd83f055d56dc7d755937800a68ad55f6047c503977c44

$ ./openshift-baremetal-install version
./openshift-baremetal-install 4.14.9
built from commit dfafb5ca972a6ed4677257aebfe4f284ac020830
release image quay.io/openshift-release-dev/ocp-release@sha256:f5eaf0248779a0478cfd83f055d56dc7d755937800a68ad55f6047c503977c44
release architecture amd64

$ sudo cp ./openshift-baremetal-install /usr/local/bin/
$ rm -f ./openshift-baremetal-install

$ openshift-baremetal-install completion bash > oinst.completion
$ sudo cp oinst.completion /etc/bash_completion.d/oinst
$ rm -f oinst.completion

NOTE: The extraction process can take up to 5 minutes, depending on your network speed and Quay.io responsiveness.

Creating Installer Configuration

Installer configuration file can be created interactively, using openshift-baremetal-install, or you can simply write it out with an editor.

Using Interactive Mode

IMPORTANT: In interactive mode, machine network (the network segment the nodes have their IPs allocated from) is expected to be 10.0.0.0/16. If your VIPs are not on that network, the installer will fail. If your machine network is not 10.0.0.0/16, the only way to install is to create install-config.yaml manually.

IMPORTANT: Interactive installer expects three control plane nodes and three workers. It will fail if you add less than three of each type of nodes to the cluster.

The interactive mode will ask you a series of questions and generate install-config.yaml at the end, but there are very few customisation options using this method.

Initially, you must select the SSH public key to be published on cluster nodes, and specify some general settings:

$ openshift-baremetal-install --dir=cluster create install-config
? SSH Public Key /home/provisioner/.ssh/id_rsa.pub
? Platform baremetal
? Provisioning Network Managed
? Provisioning Network CIDR 172.22.0.0/24
? Provisioning bridge provbr0
? Provisioning Network Interface enp0s3
? External bridge bridge0
? Add a Host:  [Use arrows to move, type to filter]
> control plane
  worker

As you can see above, after those have been answered, you may add any number of nodes, either control plane or worker.

For both type of nodes, the questions are the same:

? Add a Host: control plane
? Name controlplane1
? BMC Address ipmi://192.168.1.1:6211
? BMC Username admin
? BMC Password ********
? Boot MAC Address 52:54:00:00:fb:11
? Add another host? (y/N) y

After all the hosts have been added, there is a final series of cluster-related questions:

? Add another host? No
? Base Domain example.com
? Cluster Name mycluster
? Pull Secret [? for help] ****************************...

At this point, some checks are performed against DNS server to see if api.mycluster.example.com resolves, and if the IP is a part of the machine network. The same check is performed for the ingress VIP.

NOTE: If your VIPs are not on the default machine network, the installer will fail at this point.

FATAL failed to fetch Install Config: failed to generate asset "Install Config": invalid install config: [platform.baremetal.apiVIPs: Invalid value: "172.25.3.10": IP expected to be in one of the machine networks: 10.0.0.0/16, platform.baremetal.ingressVIPs: Invalid value: "172.25.3.11": IP expected to be in one of the machine networks: 10.0.0.0/16]

NOTE: If you added fewer than three control plane nodes, or fewer than three workers, the installer will fail at this point.

FATAL failed to fetch Install Config: failed to generate asset "Install Config": invalid install config: [...]

Creating Configuration Manually

The installer configuration file consists of a number of mandatory sections:

  • cluster domain and name
  • network settings (such as machine and cluster IP ranges)
  • control plane and compute node settings
  • infrastructure platform settings
  • pull secret and ssh key

There are also some optional sections which are useful in special cases such as disconnected installation or special install modes.

NOTE: There is an explain subcommand in the installer binary that explains the structure of the installconfig resource.

$ openshift-baremetal-install explain installconfig
KIND:     InstallConfig
VERSION:  v1

RESOURCE: <object>
  InstallConfig is the configuration for an OpenShift install.

FIELDS:
    additionalTrustBundle <string>
      AdditionalTrustBundle is a PEM-encoded X.509 certificate bundle that will be added to the nodes' trusted certificate store.
...

$ openshift-baremetal-install explain installconfig.platform.baremetal
KIND:     InstallConfig
VERSION:  v1

RESOURCE: <object>
  BareMetal is the configuration used when installing on bare metal.

FIELDS:
    apiVIP <string>
      Format: ip
      DeprecatedAPIVIP is the VIP to use for internal API communication Deprecated: Use APIVIPs

    apiVIPs <[]string>
      Format: ip
      APIVIPs contains the VIP(s) to use for internal API communication. In dual stack clusters it contains an IPv4 and IPv6 address, otherwise only one VIP
...

An example install-config.yaml for baremetal IPI looks like this:

apiVersion: v1
baseDomain: example.com
metadata:
  name: mycluster
networking:
  networkType: OVNKubernetes
  # These are the networks external IPs will be allocated from.
  machineNetwork:
    - cidr: 172.25.3.0/24
  # This is the pod network.
  clusterNetworks:
    - cidr: 10.200.0.0/14
      hostPrefix: 23
  # Only one entry is supported.
  serviceNetwork:
    - 172.30.0.0/16
compute:
- name: worker
  replicas: 2
controlPlane:
  name: master
  replicas: 3
  platform:
    baremetal: {}
platform:
  baremetal:
    apiVIPs:
      - 172.25.3.10
    ingressVIPs:
      - 172.25.3.11
    provisioningNetwork: Managed
    provisioningNetworkCIDR: 10.1.1.0/24
    provisioningDHCPRange: 10.1.1.200,10.1.1.210
    # These settings are to configure the temporary bootstrap node as a VM
    externalBridge: bridge0
    externalMACAddress: '52:54:00:00:fa:0f'
    bootstrapProvisioningIP: 10.1.1.9
    provisioningBridge: provbr0
    provisioningNetworkInterface: ens3
    provisioningMACAddress: '52:54:00:00:fb:0f'
    # This needs to be done to avoid nested virtualisation if provisioner is a VM.
    libvirtURI: qemu+ssh://root@hypervisor.example.com/system
    hosts:
      - name: controlplane1
        role: master
        bmc:
          address: ipmi://hypervisor.example.com:6211
          disableCertificateVerification: true
          username: admin
          password: password
        # This is the provisioning network interface.
        bootMACAddress: 52:54:00:00:fb:11
        bootMode: legacy
        # We need this for proper targetting of root device (vda).
        hardwareProfile: libvirt
      - name: controlplane2
        role: master
        bmc:
          address: ipmi://hypervisor.example.com:6212
          disableCertificateVerification: true
          username: admin
          password: password
        bootMACAddress: 52:54:00:00:fb:12
        bootMode: legacy
        hardwareProfile: libvirt
      - name: controlplane3
        role: master
        bmc:
          address: ipmi://hypervisor.example.com:6213
          disableCertificateVerification: true
          username: admin
          password: password
        bootMACAddress: 52:54:00:00:fb:13
        bootMode: legacy
        hardwareProfile: libvirt
      - name: worker1
        role: master
        bmc:
          address: ipmi://hypervisor.example.com:6221
          disableCertificateVerification: true
          username: admin
          password: password
        bootMACAddress: 52:54:00:00:fb:21
        bootMode: legacy
        hardwareProfile: libvirt
      - name: worker2
        role: master
        bmc:
          address: ipmi://hypervisor.example.com:6222
          disableCertificateVerification: true
          username: admin
          password: password
        bootMACAddress: 52:54:00:00:fb:22
        bootMode: legacy
        hardwareProfile: libvirt
pullSecret: '{"auths":{"cloud.openshift.com":{"auth":"...","email":"..."},"quay.io":{"auth":"...","email":"..."},...}}'
sshKey: "ssh-rsa ..."

Somewhere between RHCOS 4.12 and 4.14 the network devices stopped using the PCI naming scheme (in VMs only?). Consequently, NetworkManager-wait-online will fail because it's looking for a device (enp0s3) that isn't there (it's now called ens3). Sure, it's got an altname of enp0s3 but NetworkManager don't care.

$ ip ad sh enp0s3
2: ens3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:00:fa:13 brd ff:ff:ff:ff:ff:ff
    altname enp0s3
    inet 172.25.3.13/24 brd 172.25.3.255 scope global dynamic noprefixroute ens3
       valid_lft 86083sec preferred_lft 86083sec
    inet6 fe80::a30:57dd:ee31:e42e/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

In turn, that will break most of the rest of the installation. Go figure. Just call the interface ens3 and move on.

Installation

With the above installation configuration file created, place a copy of it in a subdirectory, such as ./mycluster/ and run the installer.

$ mkdir mycluster
$ cp install-config.yaml ./mycluster/

$ openshift-baremetal-install --dir=./mycluster/ --log-level=debug create cluster
DEBUG OpenShift Installer 4.14.9
DEBUG Built from commit dfafb5ca972a6ed4677257aebfe4f284ac020830
DEBUG Fetching Metadata...
DEBUG Loading Metadata...
...
DEBUG   Loading Install Config...
DEBUG   Loading Bootstrap Ignition Config...
...
INFO Consuming Install Config from target directory
...
INFO Obtaining RHCOS image file from 'https://rhcos.mirror.openshift.com/art/storage/prod/streams/4.14-9.2/builds/414.92.202310210434-0/x86_64/rhcos-414.92.202310210434-0-qemu.x86_64.qcow2.gz?sha256=aab55f3ee088b88562f8fdcde5be78ace023e06fa01263e7cb9de2edc7131d6f'
...
INFO Creating infrastructure resources...
...

When you see the above message, check the hypervisor for the presence of the temporary bootstrap VM.

$ virsh list
 Id   Name                      State
---------------------------------------
 4    provisioner               running
 5    mycluster-tmkmv-bootstrap running

Once you see the VM running, you can inspect any containers on it by using the SSH key configured in install config to log into it and having a look around.

$ ssh -i ~/.ssh/id_rsa core@bootstrap.mycluster.example.com
The authenticity of host 'bootstrap.mycluster.example.com (172.25.3.9)' can't be established.
...
Red Hat Enterprise Linux CoreOS 414.92.202310210434-0
  Part of OpenShift 4.14, RHCOS is a Kubernetes native operating system
  managed by the Machine Config Operator (`clusteroperator/machine-config`).

WARNING: Direct SSH access to machines is not recommended; instead,
make configuration changes via `machineconfig` objects:
...
[core@localhost ~]$ sudo -i

[root@localhost ~]# systemctl is-active crio
active

[root@localhost ~]# systemctl is-active bootkube
active

[root@localhost ~]# podman ps
CONTAINER ID  IMAGE                                                      COMMAND          CREATED             STATUS             PORTS       NAMES
da3b3e74fc7f  quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:...  /bin/rundnsmasq  About a minute ago  Up About a minute              dnsmasq

[root@localhost ~]# crictl pods
POD ID              CREATED             STATE               NAME                                          NAMESPACE           ATTEMPT             RUNTIME
af9df933d3b91       49 seconds ago      Ready               etcd-bootstrap-member-localhost.localdomain   openshift-etcd      0                   (default)

[root@localhost ~]# crictl ps
CONTAINER           IMAGE                                                     CREATED        STATE    NAME      ATTEMPT   POD ID         POD
9ad74f6433a33       753b0a16ba606f4c579690ed0035..                            6 seconds ago  Running  etcd      0         af9df933d3b91  etcd-bootstrap-member-localhost.localdomain
5c9371b25e646       quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:... 6 seconds ago  Running  etcdctl   0         af9df933d3b91  etcd-bootstrap-member-localhost.localdomain

Once you see pods like kube-system, openshift-kube-apiserver, and openshift-cluster-version show up in ready state, you can leave the shell and use the generated kubeconfig file to track the progress of the installation from the provisioner machine.

$ export KUBECONFIG=$(pwd)/cluster/auth/kubeconfig

$ oc get clusterversion
NAME      VERSION   AVAILABLE   PROGRESSING   SINCE   STATUS
version             False       True          15m     Unable to apply 4.14.9: an unknown error has occurred: MultipleErrors

$ oc get clusteroperators
$ oc get co
NAME                                       VERSION   AVAILABLE   PROGRESSING   DEGRADED   SINCE   MESSAGE
authentication
baremetal
cloud-controller-manager
cloud-credential                                     True        False         False      15m
cluster-autoscaler
config-operator
console
control-plane-machine-set
csi-snapshot-controller
dns
etcd
image-registry
ingress
insights
kube-apiserver
kube-controller-manager
kube-scheduler
kube-storage-version-migrator
machine-api
machine-approver
machine-config
marketplace
monitoring
network
node-tuning
openshift-apiserver
openshift-controller-manager
openshift-samples
operator-lifecycle-manager
operator-lifecycle-manager-catalog
operator-lifecycle-manager-packageserver
service-ca
storage

NOTE: It is normal for cluster version and various cluster operators to report transient error states as the progress of one impacts the progress of others. Eventually all these errors should go away.

Post-Install Smoke Tests

Conclusion